[FLINK-1622] Add GroupReducePartial Operator

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Implemented
• Affects Version/s: 0.9
• Fix Version/s: 0.9
• Component/s: Runtime / Task
• Assignee: Maximilian Michels
• Reporter: Aljoscha Krettek
• Created: 02/Mar/15 09:57
• Updated: 18/Mar/15 17:47
• Resolved: 18/Mar/15 17:47

Description

This does what a Reduce or GroupReduce Operator does, except it is only performed on a local partition.

This is also similar to an explicit combine that can output a type that is different from the input.