Balazs Jeszenszky has posted comments on this change. ( http://gerrit.cloudera.org:8080/8136 )
Change subject: IMPALA-5310: Add COMPUTE STATS TABLESAMPLE. ...................................................................... Patch Set 1: (4 comments) http://gerrit.cloudera.org:8080/#/c/8136/1//COMMIT_MSG Commit Message: http://gerrit.cloudera.org:8080/#/c/8136/1//COMMIT_MSG@24 PS1, Line 24: Limitations add: only for HDFS tables http://gerrit.cloudera.org:8080/#/c/8136/1//COMMIT_MSG@25 PS1, Line 25: --enable_stats_extrapolation=true Is this really required to be a startup option, wouldn't a query option (SET) work? I expect it will be enabled most of the time, and disabling it would be a troubleshooting step or workaround for some issues, particularly in planning. It would be better not to have to restart to do that. http://gerrit.cloudera.org:8080/#/c/8136/1/fe/src/main/java/org/apache/impala/analysis/ComputeStatsStmt.java File fe/src/main/java/org/apache/impala/analysis/ComputeStatsStmt.java: http://gerrit.cloudera.org:8080/#/c/8136/1/fe/src/main/java/org/apache/impala/analysis/ComputeStatsStmt.java@67 PS1, Line 67: Stats extrapolation disabled How would Impala behave if stats are computed with TABLESAMPLE, and then stats extrapolation is disabled? http://gerrit.cloudera.org:8080/#/c/8136/1/fe/src/main/java/org/apache/impala/planner/HdfsScanNode.java File fe/src/main/java/org/apache/impala/planner/HdfsScanNode.java: http://gerrit.cloudera.org:8080/#/c/8136/1/fe/src/main/java/org/apache/impala/planner/HdfsScanNode.java@777 PS1, Line 777: if (totalBytes_ == 0) { totalBytes_ doesn't get a new value in the above section, why not make this check at the beginning, as it was? -- To view, visit http://gerrit.cloudera.org:8080/8136 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-MessageType: comment Gerrit-Change-Id: I7f3e72471ac563adada4a4156033a85852b7c8b7 Gerrit-Change-Number: 8136 Gerrit-PatchSet: 1 Gerrit-Owner: Alex Behm <alex.b...@cloudera.com> Gerrit-Reviewer: Balazs Jeszenszky <jes...@gmail.com> Gerrit-Reviewer: Dimitris Tsirogiannis <dtsirogian...@cloudera.com> Gerrit-Reviewer: Vuk Ercegovac <vercego...@cloudera.com> Gerrit-Comment-Date: Wed, 27 Sep 2017 09:58:19 +0000 Gerrit-HasComments: Yes
