Why does Hive not use calcite in adaptor way?

I have read the design doc of the Hive planner recently. I've found the Hive only uses calcite as a SQL optimizer. Translate the optimized relnode to hive operator tree, and then transfer it to the Tez execution DAG. [image: image.png] Why not implement the calcite adaptor, this way is easier to us

[Question]Why does Hive not use calcite in adaptor way?

I have read the design doc of the Hive planner recently. I've found the Hive only uses calcite as a SQL optimizer. Translate the optimized relnode to hive operator tree, and then transfer it to the Tez execution DAG. Why not implement the calcite adaptor, this way is easier to use calcite? The lin