[CALCITE-482] Implement sql and planner hints

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 1.0.0-incubating
• Labels: pull-request-available
• Assignee: Danny Chan
• Reporter: Vladimir Sitnikov
• Created: 26/Nov/14 17:54
• Updated: 26/Aug/19 07:27

Description

Query optimizer can never be perfect, so it makes sense to implement hints to allow user better control the execution.

For instance: "never merge this subquery with others" (`/+ no_merge/`), "treat those tables as leading ones" (`/*+ leading */`), etc.
Hints would enable predictable performance and the planning time would be improved as well.

Issue Links

• is duplicated by: CALCITE-495 Support hints to be passed through select/DML commands
• is related to: CALCITE-299 Divide the join graph into partitions that can be optimized separately
• is related to: CALCITE-481 Add "Spool" operator, to allow re-use of relational expressions
• links to: GitHub Pull Request #1354
• links to: Implement SQL and Planner Hints In Calcite