GitHub user ManoharVanam opened a pull request:
https://github.com/apache/carbondata/pull/1693
[CARBONDATA-1909] Load is failing during insert into operation when load is
concurrently done to source table
Load is failing during insert into operation when load is concurrently done
to source table
Scenario:
Client1:
1. Create source table
2. load big data
Client2:
1. create table t1
2. insert into t1 select * from source table - load fails
Data Load:
Step1 : Dictionary Generarion
Step2: Loading data
Assume 100 records is read from source table using select statement, but
when execution reaches step2, 50 more records has been added to source table.
So when select happens on source table during data loading , it gets new record
for which dictionary is not generated. So there is inconsistency.
Solution :
To solve this issue we persisted dataframe, so that select will not get
fired for second time. But this has some performance impact. So we are
providing configuration to enable persist, if user wants to perform this kind
of scenario he can enable this configuration at cost of performance.
Be sure to do all of the following checklist to help us incorporate
your contribution quickly and easily:
- [ ] Any interfaces changed?
- [ ] Any backward compatibility impacted?
- [ ] Document update required?
- [ ] Testing done
Please provide details on
- Whether new unit test cases have been added or why no new tests
are required?
- How it is tested? Please attach test report.
- Is it a performance related change? Please attach the performance
test report.
- Any additional information to help reviewers in testing this
change.
- [ ] For large changes, please consider breaking it into sub-tasks under
an umbrella JIRA.
You can merge this pull request into a Git repository by running:
$ git pull https://github.com/ManoharVanam/incubator-carbondata pr1
Alternatively you can review and apply these changes as the patch at:
https://github.com/apache/carbondata/pull/1693.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 #1693
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commit d9c2f21a4db8115cf97cb6c073e44d43bc90d9b8
Author: Manohar <manohar.crazy09@...>
Date: 2017-12-20T09:39:45Z
Load is failing during insert into operation when load is concurrently done
to source table
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