executor-and-planner

To add a new PostgreSQL executor node safely, synchronize all four required trees: Plan, PlanState, Path, and dispatch switches. Adhering to strict node-tagging conventions and memory context discipline prevents unrecognized node type errors during query execution.

The PostgreSQL query planner integrates with the executor by requiring new Path and Plan types to have correct cost estimation and EXPLAIN wiring. This ensures the planner's path generation and the executor's node dispatching remain synchronized across the query execution pipeline.

Unrecognized node type errors in PostgreSQL internals are caused by tight coupling between the planner's path generation and the executor's node dispatching. Failing to update node tags or maintain memory context discipline when adding plan nodes triggers these runtime crashes.

The correct lifecycle for a PostgreSQL custom scan node requires structured initialization, execution, and teardown phases. Implementing the necessary Plan and PlanState structures while maintaining memory context compatibility ensures the custom scan node executes properly within the query pipeline.

Yes, you can adjust the PostgreSQL query planner cost model when implementing new Path types. Correct cost estimation and proper EXPLAIN wiring are required to ensure the new path type integrates with the existing planner and executor subsystems without runtime errors.

Yes, C programming experience is required to modify the PostgreSQL executor and planner subsystems. Tasks involve adding new plan nodes, path types, and cost model adjustments within the PostgreSQL source tree, demanding adherence to strict node-tagging conventions and memory context discipline.