[IGNITE-18390] Calcite engine. Reduce count of created spools during planning

• Type: Improvement
• Status: In Progress
• Priority: Major
• Resolution: Unresolved
• Labels: calcite calcite2-required ise
• Ignite Flags: Release Notes Required
• Assignee: Aleksey Plekhanov
• Reporter: Aleksey Plekhanov
• Created: 13/Dec/22 08:27
• Updated: 13/Jun/23 17:43

Description

Currently, when trying to convert traits table spool is created for each exchange node, but not always required. Root node not required to be rewindable, rewindability is required only on the right hand of correlated nested loop node, but rewindability trait is propagated from the bottom nodes (table and index scans) to the top nodes and all nodes are converted to rewindable, this cause redundant spool creation.

Investigate posibility to reduce count of table spools to reduce planning time.

Issue Links

• is part of: IGNITE-12248 Apache Calcite based query execution engine
• links to: GitHub Pull Request #10432