[FLINK-2871] Add OuterJoin strategy with HashTable on outer side

• Type: New Feature
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 0.10.0
• Fix Version/s: 1.0.0
• Component/s: API / DataSet, Runtime / Task
• Assignee: Chengxiang Li
• Reporter: Fabian Hueske
• Created: 19/Oct/15 16:16
• Updated: 28/Feb/19 14:30
• Resolved: 27/Jan/16 03:47

Description

Outer joins are currently supported with two local execution strategies:

• sort-merge join
• hash join where the hash table is built on the inner side. Hence, this strategy is only supported for left and right outer joins.

In order to support hash-tables on the outer side, we need a special hash table implementation that gives access to all records which have not been accessed during the probe phase.