PostgreSQL query planner parameters and prepared statements

PostgreSQL provides several planner configuration parameters, such as enable_seqscan and enable_indexscan, that influence how execution plans are generated. These settings affect planning, not the execution of an already-generated plan. With prepared statements, this raises an interesting question. Should planner settings be applied before PREPARE, before EXECUTE, or both?

Let's look at a simple example: a "tasks" table with a due date and a "done" status:

drop table if exists tasks;

-- a table of tasks with status (done or not) and due date

PostgreSQL query planner parameters and prepared statements

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