Investigate and propose Adaptive Join

Feature Request

Is your feature request related to a problem? Please describe:

Sometimes optimizer need defer the choise of Hash Join or Index Nested loops Join because it does not have a deterministic statistics.

Describe the feature you'd like:

We need someone who is familiar with planner and executor to drive and propose a plan, and see how we can be benefited with Adaptive Join.

Describe alternatives you've considered:

Teachability, Documentation, Adoption, Migration Strategy:

• https://docs.microsoft.com/en-us/sql/relational-databases/performance/joins?view=sql-server-ver15#adaptive
• https://docs.oracle.com/database/121/TGSQL/tgsql_optcncpt.htm#GUID-FA5123F0-85A8-47A6-9706-E3FE67B54A50