Support generating leading and hash_join_build hint for quick binding

[time-and-fate]

Enhancement

In tidb, the create binding from history using plan digest ... functionality relies on the ability of extracting hints from a physical plan.

Current implementation of that module only supports several simple kinds of hints. And we also find it may not be a good idea to implement this functionality in this way.

For now, one important missing hint is leading(), which is the join order hint. We want to enhance this module based on current implementation to support leading(), and also try to generate hash_join_build() hint to replace current hash_join() hint when possible. We may design better method to support this functionality in the future.

[time-and-fate]

Tests

For the SQL patterns or cases below, CREATE BINDING FROM HISTORY USING PLAN DIGEST should successfully create bindings with correct leading() and hash_join_build() hints.

• Join 4 tables with join keyword in the same query block.
• Join one table with itself by using table alias in the same query block.
• Mix normal join and join converted from IN subquery.
• DML statements.