Qifan Chen has posted comments on this change. ( http://gerrit.cloudera.org:8080/18327 )
Change subject: IMPALA-11123: Optimize count(star) for ORC scans ...................................................................... Patch Set 3: (1 comment) One more thing to check. Sorry I did not mention it yesterday. http://gerrit.cloudera.org:8080/#/c/18327/3/testdata/workloads/functional-planner/queries/PlannerTest/orc-stats-agg.test File testdata/workloads/functional-planner/queries/PlannerTest/orc-stats-agg.test: http://gerrit.cloudera.org:8080/#/c/18327/3/testdata/workloads/functional-planner/queries/PlannerTest/orc-stats-agg.test@82 PS3, Line 82: cardinality=4.39K We may need to compute the cardinality differently for count star optimization since the actual value should be # of files. Please refer to HfdsScanNode.computeCardinalities(). With the modified cardinality, a serial plan should be sufficient even for a very large table. -- To view, visit http://gerrit.cloudera.org:8080/18327 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-MessageType: comment Gerrit-Change-Id: I0fafa1182f97323aeb9ee39dd4e8ecd418fa6091 Gerrit-Change-Number: 18327 Gerrit-PatchSet: 3 Gerrit-Owner: Riza Suminto <riza.sumi...@cloudera.com> Gerrit-Reviewer: Csaba Ringhofer <csringho...@cloudera.com> Gerrit-Reviewer: Impala Public Jenkins <impala-public-jenk...@cloudera.com> Gerrit-Reviewer: Qifan Chen <qc...@cloudera.com> Gerrit-Reviewer: Quanlong Huang <huangquanl...@gmail.com> Gerrit-Reviewer: Riza Suminto <riza.sumi...@cloudera.com> Gerrit-Comment-Date: Wed, 23 Mar 2022 18:32:37 +0000 Gerrit-HasComments: Yes
