[HIVE-21006] Extend SharedWorkOptimizer to remove semijoins when there is a reutilization opportunity

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 4.0.0-alpha-1
• Component/s: Physical Optimizer
• Assignee: Jesús Camacho Rodríguez
• Reporter: Jesús Camacho Rodríguez
• Created: 05/Dec/18 04:19
• Updated: 27/Feb/24 22:24
• Resolved: 06/Dec/18 00:43

Description

Assume there are two TS operators in the plan over the same table, same columns, same conditions, etc.
The first TS operator, TS1, has an incoming SJ edge. The second TS operator, TS2, does not have any incoming SJ edge.
Since TS2 is reading the full table, we may just remove the SJ and TS1. Then we will keep and share TS2, since it reads all the data in any case.

Issue Links

• links to: RB link