GitHub user xuchuanyin opened a pull request:
https://github.com/apache/carbondata/pull/2410
[CARBONDATA-2650][Datamap] Fix bugs in negative number of skipped blocklets
Currently in carbondata, default blocklet datamap will be used to prune
blocklets. Then other indexdatamap will be used.
But the other index datamap works for segment scope, which in some
scenarios, the size of pruned result will be bigger than that of default
datamap, thus causing negative number of skipped blocklets in explain
query output.
Here we add intersection after pruning. If the pruned result size is
zero, we will finish the pruning.
Be sure to do all of the following checklist to help us incorporate
your contribution quickly and easily:
- [x] Any interfaces changed?
`NO`
- [x] Any backward compatibility impacted?
`NO`
- [ ] Document update required?
`NO`
- [ ] Testing done
Please provide details on
- Whether new unit test cases have been added or why no new tests
are required?
`NO, tests will be added in another PR`
- How it is tested? Please attach test report.
`Tested in local`
- Is it a performance related change? Please attach the performance
test report.
`NO`
- Any additional information to help reviewers in testing this
change.
`NA`
- [x] For large changes, please consider breaking it into sub-tasks under
an umbrella JIRA.
`NA`
You can merge this pull request into a Git repository by running:
$ git pull https://github.com/xuchuanyin/carbondata
issue_2650_negative_skipped_blocklets
Alternatively you can review and apply these changes as the patch at:
https://github.com/apache/carbondata/pull/2410.patch
To close this pull request, make a commit to your master/trunk branch
with (at least) the following in the commit message:
This closes #2410
----
commit a6508af91211c2b005a33bed4db2a7964bb27af6
Author: xuchuanyin <xuchuanyin@...>
Date: 2018-06-26T06:11:17Z
Fix bugs in negative number of skipped blocklets
Currently in carbondata, default blocklet datamap will be used to prune
blocklets. Then other indexdatamap will be used.
But the other index datamap works for segment scope, which in some
scenarios, the size of pruned result will be bigger than that of default
datamap, thus causing negative number of skipped blocklets in explain
query output.
Here we add intersection after pruning. If the pruned result size is
zero, we will finish the pruning.
----
---
