Dimitris Tsirogiannis has posted comments on this change. Change subject: IMPALA-5547: Rework FK/PK join detection. ......................................................................
Patch Set 2: (8 comments) http://gerrit.cloudera.org:8080/#/c/7257/2/fe/src/main/java/org/apache/impala/planner/HashJoinNode.java File fe/src/main/java/org/apache/impala/planner/HashJoinNode.java: PS2, Line 27: import org.apache.impala.analysis.SlotDescriptor; Is this used? PS2, Line 40: import org.apache.kudu.shaded.com.google.common.base.Joiner; replace http://gerrit.cloudera.org:8080/#/c/7257/2/fe/src/main/java/org/apache/impala/planner/JoinNode.java File fe/src/main/java/org/apache/impala/planner/JoinNode.java: PS2, Line 79: - nit: remove PS2, Line 80: ordered based on the tuple ids I am not sure I get what that ordering is. Do you mean grouped? PS2, Line 202: based on the single most : * selective join predicate. We do not attempt to estimate the joint selectivity of : * multiple join predicates to avoid underestimation. Much better. Thanks PS2, Line 280: fkPkCandidate.get(0) Can you plz explain this? I could be wrong about this but it seems that the decision of whether this is a pk/fk depends on which equi-join slots we process first. Maybe I am missing something. In either case, plz add a comment. PS2, Line 299: Preconditions.checkState(lhsCard >= 0 && rhsCard >= 0); Are we certain this is a valid precondition check? Why isn't a 0 rhsCard possible? Unless this is guaranteed to be the case... PS2, Line 337: we adjustments nit: grammar -- To view, visit http://gerrit.cloudera.org:8080/7257 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-MessageType: comment Gerrit-Change-Id: I49074fe743a28573cff541ef7dbd0edd88892067 Gerrit-PatchSet: 2 Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-Owner: Alex Behm <alex.b...@cloudera.com> Gerrit-Reviewer: Alex Behm <alex.b...@cloudera.com> Gerrit-Reviewer: Dimitris Tsirogiannis <dtsirogian...@cloudera.com> Gerrit-Reviewer: Mostafa Mokhtar <mmokh...@cloudera.com> Gerrit-Reviewer: Zach Amsden <zams...@cloudera.com> Gerrit-HasComments: Yes
