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Hive QA commented on HIVE-21690: -------------------------------- | (x) *{color:red}-1 overall{color}* | \\ \\ || Vote || Subsystem || Runtime || Comment || || || || || {color:brown} Prechecks {color} || | {color:green}+1{color} | {color:green} @author {color} | {color:green} 0m 0s{color} | {color:green} The patch does not contain any @author tags. {color} | || || || || {color:brown} master Compile Tests {color} || | {color:green}+1{color} | {color:green} mvninstall {color} | {color:green} 8m 45s{color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} compile {color} | {color:green} 1m 8s{color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} checkstyle {color} | {color:green} 0m 41s{color} | {color:green} master passed {color} | | {color:blue}0{color} | {color:blue} findbugs {color} | {color:blue} 4m 14s{color} | {color:blue} ql in master has 2253 extant Findbugs warnings. {color} | | {color:green}+1{color} | {color:green} javadoc {color} | {color:green} 1m 0s{color} | {color:green} master passed {color} | || || || || {color:brown} Patch Compile Tests {color} || | {color:green}+1{color} | {color:green} mvninstall {color} | {color:green} 1m 28s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} compile {color} | {color:green} 1m 8s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} javac {color} | {color:green} 1m 8s{color} | {color:green} the patch passed {color} | | {color:red}-1{color} | {color:red} checkstyle {color} | {color:red} 0m 39s{color} | {color:red} ql: The patch generated 1 new + 7 unchanged - 0 fixed = 8 total (was 7) {color} | | {color:green}+1{color} | {color:green} whitespace {color} | {color:green} 0m 0s{color} | {color:green} The patch has no whitespace issues. {color} | | {color:green}+1{color} | {color:green} findbugs {color} | {color:green} 4m 24s{color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} javadoc {color} | {color:green} 1m 0s{color} | {color:green} the patch passed {color} | || || || || {color:brown} Other Tests {color} || | {color:green}+1{color} | {color:green} asflicense {color} | {color:green} 0m 14s{color} | {color:green} The patch does not generate ASF License warnings. {color} | | {color:black}{color} | {color:black} {color} | {color:black} 25m 9s{color} | {color:black} {color} | \\ \\ || Subsystem || Report/Notes || | Optional Tests | asflicense javac javadoc findbugs checkstyle compile | | uname | Linux hiveptest-server-upstream 3.16.0-4-amd64 #1 SMP Debian 3.16.43-2+deb8u5 (2017-09-19) x86_64 GNU/Linux | | Build tool | maven | | Personality | /data/hiveptest/working/yetus_PreCommit-HIVE-Build-17118/dev-support/hive-personality.sh | | git revision | master / 341fc33 | | Default Java | 1.8.0_111 | | findbugs | v3.0.0 | | checkstyle | http://104.198.109.242/logs//PreCommit-HIVE-Build-17118/yetus/diff-checkstyle-ql.txt | | modules | C: ql U: ql | | Console output | http://104.198.109.242/logs//PreCommit-HIVE-Build-17118/yetus.txt | | Powered by | Apache Yetus http://yetus.apache.org | This message was automatically generated. > Support outer joins with HiveAggregateJoinTransposeRule and turn it on by > default > --------------------------------------------------------------------------------- > > Key: HIVE-21690 > URL: https://issues.apache.org/jira/browse/HIVE-21690 > Project: Hive > Issue Type: Improvement > Components: Query Planning > Reporter: Vineet Garg > Assignee: Vineet Garg > Priority: Major > Attachments: HIVE-21690.1.patch > > > 1) This optimization is off by default. We would like to turn on this > optimization wherein group by is pushed down to join, in some cases top > aggregate is removed but in most of the cases this optimization adds extra > aggregate nodes. To measure if those extra aggregates are beneficial or not > (they might add extra overhead without reducing rows) cost is computed and > compared b/w previous plan and new plan. > Since Hive's cost model only consider JOIN's cost and discard cost of rest of > the nodes, this comparison always favor new plan (since adding aggregate > beneath join reduces the total number of rows processed by the join and > therefore reduces the join cost). Therefore turning on this optimization with > existing cost model is not a good idea. > One approach to fix this is to localize the cost computation to the rule > itself, i.e compute the non-cumulative cost of existing aggregate and join > and compare it with new cost of new aggregates, join and top aggregate. > Better approach in my opinion would be to fix the cost model and take > aggregate cost into account (along with the join). This could affect other > queries and can cause performance regression but those will most likely be > issues with the planning and should be investigated and fixed. > 2) This optimization currently only support INNER JOIN. This can be extended > to support OUTER joins. -- This message was sent by Atlassian JIRA (v7.6.3#76005)