Module aggregation 

Aggregation and GROUP BY Execution

This module implements aggregation with GROUP BY and HAVING clauses:

• Global aggregation (without GROUP BY): SELECT COUNT(*) FROM table
• Grouped aggregation: SELECT category, SUM(amount) FROM sales GROUP BY category
• HAVING clause: SELECT category, SUM(amount) FROM sales GROUP BY category HAVING SUM(amount) > 100

Re-exports

pub use super::utils::expression_contains_aggregate;

pub use super::utils::is_aggregate_function;

Structs

AggregationExecutor

Single owner for aggregate planning, state, execution and finalization.

SqlAggregateFunction

Represents an aggregate function call in a SELECT list

Enums

DerivedAggregationAttempt

Outcome of trying the streaming aggregate path for a derived source.

GroupByItem

Represents a GROUP BY item - either a column reference or an expression

Traits

AggregationExecutorExt

Internal call surface between aggregation phases and the SELECT owner.

AggregationHost

Narrow composition contract for the remaining correlated-subquery hooks. Storage and function dependencies stay explicit and downward-only.