[
https://issues.apache.org/jira/browse/TAJO-838?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14269350#comment-14269350
]
ASF GitHub Bot commented on TAJO-838:
-------------------------------------
Github user jihoonson commented on the pull request:
https://github.com/apache/tajo/pull/231#issuecomment-69185433
@hyunsik thanks for the review!
There still remains many things for efficient query processing with
indexes. Here are the significant issues.
1. Printing appropriate messages after creating an index. If the index is
successfully created, cli should show a success message. Otherwise, it should
show a failure message.
2. Index metadata backup and restore. In order to support the index restore
without recreation, we need to provide a new DDL statement, ```CREATE INDEX
[name] ON [path]```.
3. Index support for partitioned tables.
4. New index structure.
5. Other experimental issues, such as prefetching indexes, for the
performance improvement.
IMHO, after resolving the issues 1 and 2, it would be sufficient to be
merged into the master branch.
What do you think about it?
> 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)
