[CALCITE-3166] Make RelBuilder configurable

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.21.0
• Labels: pull-request-available
• Assignee: Julian Hyde
• Reporter: Julian Hyde
• Created: 02/Jul/19 00:13
• Updated: 10/Sep/19 21:36
• Resolved: 15/Jul/19 18:04

Description

Make RelBuilder configurable, so that particular optimizations can easily be turned off.

I propose to add a class RelBuilder.Config, which is immutable and has a public final field for each configuration property; also a class RelBuilder.ConfigBuilder to create a config.

RelBuilder.create(FrameworkConfig frameworkConfig) will get a config by calling frameworkConfig.getContext().unwrap(RelBuilder.Config.class).

Going forward, any new features that add "optimizations" to RelBuilder would need to have a corresponding flag in Config to switch them off. A feature would not be considered "complete" if it did not have tests and a switch.