You are viewing a plain text version of this content. The canonical link for it is here.
Posted to notifications@asterixdb.apache.org by "ASF subversion and git services (Jira)" <ji...@apache.org> on 2024/08/16 21:26:00 UTC
[jira] [Commented] (ASTERIXDB-3470) CBO estimates incorrect join cardinality with IMDb datasets
[ https://issues.apache.org/jira/browse/ASTERIXDB-3470?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17874398#comment-17874398 ]
ASF subversion and git services commented on ASTERIXDB-3470:
------------------------------------------------------------
Commit 6d17c6205fb09a4a18d4de1e833657cd74a136e0 in asterixdb's branch refs/heads/master from murali4104
[ https://gitbox.apache.org/repos/asf?p=asterixdb.git;h=6d17c6205f ]
[ASTERIXDB-3470][COMP] Correctly detect triangles in Join Graph
Change-Id: I1537b09e5d21333d0d810cc058988fcadb5192f8
Reviewed-on: https://asterix-gerrit.ics.uci.edu/c/asterixdb/+/18683
Integration-Tests: Jenkins <je...@fulliautomatix.ics.uci.edu>
Tested-by: Jenkins <je...@fulliautomatix.ics.uci.edu>
Reviewed-by: Vijay Sarathy <vi...@couchbase.com>
> CBO estimates incorrect join cardinality with IMDb datasets
> -----------------------------------------------------------
>
> Key: ASTERIXDB-3470
> URL: https://issues.apache.org/jira/browse/ASTERIXDB-3470
> Project: Apache AsterixDB
> Issue Type: Bug
> Components: COMP - Compiler
> Reporter: Mehnaz Tabassum Mahin
> Assignee: murali krishna
> Priority: Major
> Labels: triaged
> Attachments: join_queries.txt, load_and_analyze.txt, schema.txt
>
>
> The join cardinalities with IMDb datasets are *much overestimated* and the inaccuracy increases with the increase in sample sizes.
> IMDb dataset: [http://homepages.cwi.nl/~boncz/job/imdb.tgz |http://homepages.cwi.nl/~boncz/job/imdb.tgz](Please change the corresponding CSV file name to "keywords.csv")
> In the attachment, two 10-datasets join queries and the relevant DDL statements are given. Both join queries are with 10 IMDb datasets and different selectivity predicates.
> # The actual cardinality of the first join query is {*}1298{*}, where the estimated ones are:
> ** with "low" sample: 7.489 x 10{^}10{^}
> ** with "medium" sample: 5.619 x 10{^}12{^}
> ** with "high" sample: 6.022 x 10{^}12{^}
> # The actual cardinality of the second one is {*}1062{*}, whereas the estimated ones are:
> ** with "low" sample: 4.33 x 10{^}8{^}
> ** with "medium" sample: 1.479 x 10{^}11{^}
> ** with "high" sample: 1.93 x 10{^}11{^}
--
This message was sent by Atlassian Jira
(v8.20.10#820010)