Module subquery 

Subquery Execution

This module handles execution of subqueries including:

• EXISTS subqueries
• Scalar subqueries
• IN subqueries

Structs

SemiJoinInfo

Information extracted from an EXISTS subquery for semi-join optimization. Example: EXISTS (SELECT 1 FROM orders o WHERE o.user_id = u.id AND o.amount > 500)

SubqueryExecutor

Single owner for subquery rewriting, correlation analysis, cache use and semi/anti-join execution.

Traits

SubqueryExecutorExt

Internal call surface between subquery traversal and the SELECT owner.

SubqueryHost

Narrow composition contract for recursive SELECT execution. Query-local caches remain owned by ExecutionContext; the host provides only the engine and the surrounding SELECT entrypoint.