[FLINK-33028] FLIP-348: Make expanding behavior of virtual metadata columns configurable

• Type: New Feature
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.19.0
• Component/s: Table SQL / API, Table SQL / Planner
• Assignee: Timo Walther
• Reporter: Timo Walther
• Created: 04/Sep/23 12:22
• Updated: 22/Feb/24 11:30
• Resolved: 22/Feb/24 11:30

Description

Many SQL vendors expose additional metadata via so-called "pseudo columns" or "system columns" next to the physical columns.

However, those columns should not be selected by default when expanding SELECT *. Also for the sake of backward compatibility. Flink SQL already offers pseudo columns next to the physical columns exposed as metadata columns.

This proposal suggests to evolve the existing column design slightly to be more useful for platform providers.

https://cwiki.apache.org/confluence/x/_o6zDw