GitHub user xccui opened a pull request:
https://github.com/apache/flink/pull/5016
[FLINK-8069] [table] Support empty watermark strategy for TableSources
## What is the purpose of the change
This PR enables an empty watermark strategy for
`RowtimeAttributeDescriptor`.
## Brief change log
- Add a default `null` value for the watermark strategy in
`RowtimeAttributeDescriptor`.
- Add a case in `StreamTableSourceScan` for empty watermark strategy.
- Add a test case and update related docs.
## Verifying this change
The change can be verified by the new added
`testRowtimeTableSourceWithoutWMStrategy()`.
## Does this pull request potentially affect one of the following parts:
- Dependencies (does it add or upgrade a dependency): (no)
- The public API, i.e., is any changed class annotated with
`@Public(Evolving)`: (no)
- The serializers: (no)
- The runtime per-record code paths (performance sensitive): (no)
- Anything that affects deployment or recovery: JobManager (and its
components), Checkpointing, Yarn/Mesos, ZooKeeper: (no)
- The S3 file system connector: (no)
## Documentation
- Does this pull request introduce a new feature? (yes)
- If yes, how is the feature documented? (docs)
You can merge this pull request into a Git repository by running:
$ git pull https://github.com/xccui/flink FLINK-8069
Alternatively you can review and apply these changes as the patch at:
https://github.com/apache/flink/pull/5016.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 #5016
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commit ba0fc2777f2c81c582032124d301f5ee301ae009
Author: Xingcan Cui <xingc...@gmail.com>
Date: 2017-11-15T03:01:13Z
[FLINK-8069] [table] Support empty watermark strategy for TableSources
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