[FLINK-3943] Add support for EXCEPT (set minus)

• Type: New Feature
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 1.1.0
• Fix Version/s: 1.1.0
• Component/s: Table SQL / API
• Assignee: Ivan Mushketyk
• Reporter: Fabian Hueske
• Created: 20/May/16 09:35
• Updated: 11/Jul/16 14:33
• Resolved: 11/Jul/16 12:03

Description

Currently, the Table API and SQL do not support EXCEPT.

EXCEPT can be executed as a coGroup on all fields that forwards records of the first input if the second input is empty.

In order to add support for EXCEPT to the Table API and SQL we need to:

• Implement a DataSetMinus class that translates an EXCEPT into a DataSet API program using a coGroup on all fields.
• Implement a DataSetMinusRule that translates a Calcite LogicalMinus into a DataSetMinus.
• Extend the Table API (and validation phase) to provide an except() method.

Issue Links

• links to: GitHub Pull Request #2169