Thx Ruben, very appreciate for your suggestions, I will make modifications soon.
The main diff it to move semiJoin physical implementations to EnumerableHashJoin, i also see that now we use method `contains` to probe the right side(inner loop), but there also 2 implementations for `contains` One is Hash probe and one is loop look up, I’m not very sure it is indeed a hash-semi or nestedLoop-semi. [1] https://github.com/apache/calcite/blob/b03cdc486cf5c7232bbc6fa9b5f02f564e9601c3/linq4j/src/main/java/org/apache/calcite/linq4j/EnumerableDefaults.java#L1312 Best, Danny Chan 在 2019年4月18日 +0800 AM1:01，Ruben Q L <[email protected]>，写道： > Hi Danny, > thanks for kicking off this big task, I have started to add some comments > in the PR > > Best regards, > Ruben > > > Le lun. 15 avr. 2019 à 20:49, Julian Hyde <[email protected]> a écrit : > > > I haven’t reviewed the change, but let’s strike a balance between > > backwards compatibility and progress. We should allow breaking changes if > > they make a significant improvement. Of course we should mark APIs > > deprecated for one or two releases, if possible. > > > > > On Apr 15, 2019, at 2:01 AM, Yuzhao Chen <[email protected]> wrote: > > > > > > I also have this question when i was doing this patch, cause Enumerable > > nodes are physical operators(implementation) and should be specific to > > Calcite. So in the beginning i didn’t classify them as public APIs and only > > keep the constructors and methods for logical nodes. > > > > > > Well this searching is somewhat convincing, there are many > > interfaces/methods are marked as deprecated and to be removed before 2.0, > > it would be better if the principles for backward compatibility are more > > clear. > > > > > > Best, > > > Danny Chan > > > 在 2019年4月14日 +0800 PM7:41，Hongze Zhang <[email protected]>，写道： > > > > I didn't take look on the PR in detail so far, but it seems that a > > topic about backward compatibility would be worth to discuss anyway. > > > > > > > > Regarding the Enumerable's API, I don't think there are many use cases > > of them from Calcite users. Although users may create instances in some > > custom rules, or extend the Enumerable rels' classes to implement some > > specific behaviors, I am still not sure if such cases are that usual. > > > > > > > > For example, I've run a Google search for term "EnumerableJoin.create" > > on github.com, only 2 results returned[1], and both are from > > apache/calcite project. Similar result on "EnumerableCorrelate.create". I > > am pretty sure that Google could not give a precise result about code usage > > (I don't find a way to search these terms using GitHub code search), but at > > least it shows some sort of trend. As a comparison there are 33 results[2] > > for "LogicalJoin.create", some are from external projects. > > > > > > > > So my question would be: how much backward compatibility should we > > respect when we make API changes to Calcite? To me it is not much clear. I > > know compatibility is very, very important for an Apache project (see "The > > Apache Project Maturity Model/QU40"[3]), but I am not sure if we should add > > "@Depracated" to any changed public staffs, the code will be messy and hard > > to understand. > > > > > > > > Anyway my example about EnumerableJoin/Correlate just shows my > > confusion on a broader topic. So I will be +1 to the consensus that already > > be achieved so far. But I'll be happy to hear more principles on how to > > manage the backward compatibility for Calcite, such as: what's the > > definition about Calcite's public API, or what changes would be considered > > backward-incompatible, etc. I think that will also benefit our developers a > > lot. > > > > > > > > > > > > Best, > > > > Hongze > > > > > > > > > > > > [1] > > https://www.google.com/search?q=%22EnumerableJoin.create%22+site%3A%3Ahttps%3A%2F%2Fgithub.com > > > > [2] > > https://www.google.com/search?q=%22LogicalJoin.create%22+site%3A%3Ahttps%3A%2F%2Fgithub.com > > > > [3] > > https://community.apache.org/apache-way/apache-project-maturity-model.html#quality > > > > > > > > > On Apr 14, 2019, at 14:53, Walaa Eldin Moustafa > > > > > <[email protected]> > > wrote: > > > > > > > > > > Agreed, but not sure what would the best way to do it be without > > > > > making the code very confusing. > > > > > > > > > > On Sat, Apr 13, 2019 at 2:46 PM Haisheng Yuan <[email protected]> > > wrote: > > > > > > > > > > > > I share the same concern with you. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Thanks~ > > > > > > Haisheng > > Yuan------------------------------------------------------------------ > > > > > > 发件人：Stamatis Zampetakis<[email protected]> > > > > > > 日 期：2019年04月14日 05:37:29 > > > > > > 收件人：<[email protected]> > > > > > > 主 题：Re: Join, SemiJoin, Correlate > > > > > > > > > > > > Hi Danny, > > > > > > > > > > > > Thanks a lot for taking this on, it is a great start! > > > > > > > > > > > > I didn't look thoroughly through the PR but I noticed that there are > > many > > > > > > renaming/refactoring of public APIs. I am not sure if we should > > introduce > > > > > > so many breaking changes without prior notice. A most conservative > > approach > > > > > > would be to keep existing classes/methods, mark them as deprecated, > > and > > > > > > then remove them in one of the coming releases. I am not sure if > > > > > > that > > is > > > > > > the right way to go so let's see what the others have to say. > > > > > > > > > > > > Best, > > > > > > Stamatis > > > > > > > > > > > > On Fri, Apr 12, 2019 at 9:18 AM Yuzhao Chen <[email protected]> > > wrote: > > > > > > > > > > > > > Hi, @Haisheng Yuan, @Julian Hyde, @Stamatis Zampetakis, > > > > > > > @Walaa Eldin Moustafa > > > > > > > > > > > > > > I have did the work for this discussion, and look forward to your > > > > > > > suggestions. > > > > > > > > > > > > > > > > > > > > > ### Diff > > > > > > > - Deprecate SemiJoin, EquiJoin, EnumerableSemiJoin, SemiJoinType, > > > > > > > EnumerableSemiJoinRule, EnumerableThetaJoin > > > > > > > - Make EnumerableMergeJoin extends Join instead of EquiJoin > > > > > > > - Add SEMI and ANTI join type to JoinRelType, add method > > > > > > > returnsJustFirstInput() to decide if the join only outputs left > > > > > > > side > > > > > > > - Correlate use JoinRelType instead of SemiJoinType > > > > > > > - Rename EnumerableCorrelate to EnumerableNestedLoopJoin and make > > > > > > > it > > > > > > > exptends Join instead of Correlate > > > > > > > - Rename EnumerableJoin to EnumerableHashJoin > > > > > > > - EnumerableJoinRule will convert semi-join to > > EnumerableNestedLoopJoin > > > > > > > (EnumerableSemiJoin's function is merged into this rule) > > > > > > > - Add method isNonCorrelateSemiJoin() in Join.java to make sure if > > this > > > > > > > join is a semi-join (Comes from SemiJoinRule) or comes from > > > > > > > decorrelation(SubqueryRemoveRule or RelDecorrelator), the returns > > value > > > > > > > true means the join is a semi-join equivalent to SemiJoin before > > this patch. > > > > > > > - Cache the JoinInfo in Join and use it to get leftKeys and > > rightKeys, > > > > > > > merge the SemiJoin#computeSelfCost to Join#computeSelfCost > > > > > > > - RelBuilder removes SemiJoinFactory, method #semiJoin now return > > > > > > > a > > > > > > > LogicalJoin with JoinRelType#SEMI > > > > > > > > > > > > > > ### Rules tweak > > > > > > > - JoinAddRedundantSemiJoinRule now create LogicalJoin with > > > > > > > JoinRelType#SEMI instead of SemiJoin > > > > > > > - JoinToCorrelateRule remove SEMI instance and change the matchs > > condition > > > > > > > to !join.getJoinType().generatesNullsOnLeft() which also allowed > > > > > > > ANTI > > > > > > > compared before this patch. > > > > > > > - SemiJoinRule match SEMI join specificlly > > > > > > > > > > > > > > ### Metadata tweak > > > > > > > - RelMdAllPredicates, RelMdExpressionLineage: Add full rowType to > > > > > > > getAllPredicates(Join) cause semi-join only outputs one side > > > > > > > - RelMdColumnUniqueness, RelMdSelectivity, RelMdDistinctRowCount, > > > > > > > RelMdSize, RelMdUniqueKeys: merge semi-join logic to join > > > > > > > > > > > > > > > > > > > > > ### Test cases change > > > > > > > - MaterializationTest#testJoinMaterialization11 now can > > > > > > > materialize > > > > > > > successfully, cause i allow logical SemiJoin node to match, the > > original > > > > > > > matchs SemiJoin as SemiJoin.class.isAssignableFrom(), which i > > > > > > > think > > is > > > > > > > wrong cause this will only matches subClasses of SemiJoin which is > > only > > > > > > > EnumerableSemiJoin before this patch. > > > > > > > - SortRemoveRuleTest#removeSortOverEnumerableCorrelate, because > > > > > > > CALCITE-2018, the final EnumerableSort's cost was cache by the > > previous > > > > > > > EnumerableSort with logical childs, so i remove the > > EnumerableSortRule and > > > > > > > the best plan is correct > > > > > > > - sub-query.iq has better plan for null correlate > > > > > > > > > > > > > > > > > > > > > > > > > > > > Best, > > > > > > > Danny Chan > > > > > > > 在 2019年3月21日 +0800 AM3:07，Julian Hyde <[email protected]>，写道： > > > > > > > > I just discovered that Correlate, which is neither a Join nor a > > > > > > > SemiJoin, uses SemiJoinType, but SemiJoin does not use > > > > > > > SemiJoinType. > > > > > > > > > > > > > > > > Yuck. The Join/SemiJoin/Correlate type hierarchy needs some > > > > > > > > thought. > > > > > > > > > > > > > > > > Julian > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >
