[SOLR-16239] Add Join query plans to Solr SQL

• Type: New Feature
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: Parallel SQL
• Labels: RobustSQL
• Assignee: Unassigned
• Reporter: Joel Bernstein
• Created: 06/Jun/22 13:36
• Updated: 22/Jun/22 17:36

Description

This is an umbrella ticket for adding join query plans for Solr SQL.

Solr 9 adds significant performance improvements to the export handler. These improvements were done in part to support fast distributed joins in Solr SQL.

Streaming Expressions already supports hash joins and merge joins and has limited support for nested loop joins (fetch). What needs to be done is to add Rules to the Calcite planner that push the joins down to the SQL handler.

Calcite also has the ability to execute joins so part of this work will also be to gracefully fall back to Calcite's join engine.

Issue Links

• requires: SOLR-16243 Compile SQL to a Streaming Expression while visiting the Calcite SQL parse tree