[
https://issues.apache.org/jira/browse/TAJO-838?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14163746#comment-14163746
]
ASF GitHub Bot commented on TAJO-838:
-------------------------------------
Github user hyunsik commented on the pull request:
https://github.com/apache/tajo/pull/192#issuecomment-58388360
Looks very interesting. Please keep going. Although, as we know, index is
only useful in the case where the selectivity is low, it has great potential to
boost up performance. If we give users a good guide, index can be a killer
feature in this field.
Could you let us know index size and data volume? My primary concern on the
current implementation is the index file structure (BSTIndex), which is a large
and individual file per task. If your implementation is the same, we can make
an effort to investigate its next generation index structure.
In addition, could you please update index_support branch and reupload your
patch. The differences between branch may include lots of other changes.
Thanks,
Hyunsik
> Improve query planner to utilize index
> --------------------------------------
>
> Key: TAJO-838
> URL: https://issues.apache.org/jira/browse/TAJO-838
> Project: Tajo
> Issue Type: Sub-task
> Components: planner/optimizer
> Reporter: Jihoon Son
> Assignee: Jihoon Son
> Priority: Minor
>
> Index can improve the query performance when the selectivity of query is high.
> Thus, query planner should decide whether index is used or not for a given
> query.
> The selectivity can be guessed using statistics.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
