[FLINK-3941] Add support for UNION (with duplicate elimination)

• Type: New Feature
• Status: Closed
• Priority: Minor
• Resolution: Implemented
• Affects Version/s: 1.1.0
• Fix Version/s: 1.1.0
• Component/s: Table SQL / API
• Assignee: Yijie Shen
• Reporter: Fabian Hueske
• Created: 20/May/16 09:26
• Updated: 26/May/16 15:17
• Resolved: 26/May/16 15:17

Description

Currently, only UNION ALL is supported by Table API and SQL.

UNION (with duplicate elimination) can be supported by applying a DataSet.distinct() after the union on all fields. This issue includes:

• Extending DataSetUnion
• Relaxing DataSetUnionRule to translated non-all unions.
• Extend the Table API with union() method.

Issue Links

• links to: GitHub Pull Request #2025