[IMPALA-10647] Improve always-true min/max filter handling in coordinator

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: Impala 4.0.0
• Epic Color: ghx-label-2
• Assignee: Qifan Chen
• Reporter: Qifan Chen
• Created: 08/Apr/21 16:55
• Updated: 27/Apr/21 17:11
• Resolved: 27/Apr/21 17:11

Description

Currently, when a just arriving min/max filter is the last one to arrive or is always true, the coordinator disables the corresponding filter
representation by setting it to Always True. This makes it impossible to differentiate a true AlwaysTrue filter (say, set in the
hash join building step) from the one being disabled.

A better handling is needed in this area.