Ted-Jiang opened a new pull request, #4616: URL: https://github.com/apache/arrow-datafusion/pull/4616
# Which issue does this PR close? <!-- We generally require a GitHub issue to be filed for all bug fixes and enhancements and this helps us generate change logs for our releases. You can link an issue to this PR using the GitHub syntax. For example `Closes #123` indicates that this PR will close issue #123. --> Closes #4603. # Rationale for this change There are three kind of window: 1. `RANGE BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING`: compute once. 2. `RANGE BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW`: use Aggregator compute cumulative state 3. `ROWS BETWEEN 3 PRECEDING AND 3 FOLLOWING`: need Aggregator support remove sub-state, for now min max not support this `remove` operator From [paper](http://www.vldb.org/pvldb/vol8/p1058-leis.pdf) `For aggregate functions like min, max, count, and sum, the Segment Tree uses the obvious corresponding aggregate function`. So i try to use `segment-tree` to support this. # What changes are included in this PR? <!-- There is no need to duplicate the description in the issue here but it is sometimes worth providing a summary of the individual changes in this PR. --> # Are these changes tested? <!-- We typically require tests for all PRs in order to: 1. Prevent the code from being accidentally broken by subsequent changes 3. Serve as another way to document the expected behavior of the code If tests are not included in your PR, please explain why (for example, are they covered by existing tests)? --> # Are there any user-facing changes? <!-- If there are user-facing changes then we may require documentation to be updated before approving the PR. --> <!-- If there are any breaking changes to public APIs, please add the `api change` label. --> -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
