[FLINK-18784] Push Projection through WatermarkAssigner

• Type: Sub-task
• Status: Closed
• Priority: Major
• Resolution: Implemented
• Component/s: Table SQL / Planner
• Assignee: Unassigned
• Reporter: Jark Wu
• Created: 31/Jul/20 10:34
• Updated: 17/Nov/20 14:31
• Resolved: 17/Nov/20 14:31

Description

Currently, a projection on a watermark table can't push the projection into the source, this is because the projection can't be pushed down throgh watermark node.

Calc(select=[a, b, rowtime])
            :     +- WatermarkAssigner(rowtime=[rowtime], watermark=[rowtime])
            :        +- Calc(select=[a, b, c, PROCTIME() AS proctime, rowtime])
            :           +- TableSourceScan(table=[[default_catalog, default_database, wmTable1]], fields=[a, b, c, rowtime])