postgresql/src/include/lib/knapsack.h

/*
 * knapsack.h
 *
 * Copyright (c) 2017-2025, PostgreSQL Global Development Group
 *
 * src/include/lib/knapsack.h
 */
#ifndef KNAPSACK_H
#define KNAPSACK_H

#include "nodes/bitmapset.h"

extern Bitmapset *DiscreteKnapsack(int max_weight, int num_items,
								   int *item_weights, double *item_values);

#endif							/* KNAPSACK_H */
Support hashed aggregation with grouping sets. This extends the Aggregate node with two new features: HashAggregate can now run multiple hashtables concurrently, and a new strategy MixedAggregate populates hashtables while doing sorted grouping. The planner will now attempt to save as many sorts as possible when planning grouping sets queries, while not exceeding work_mem for the estimated combined sizes of all hashtables used. No SQL-level changes are required. There should be no user-visible impact other than the new EXPLAIN output and possible changes to result ordering when ORDER BY was not used (which affected a few regression tests). The enable_hashagg option is respected. Author: Andrew Gierth Reviewers: Mark Dilger, Andres Freund Discussion: https://postgr.es/m/87vatszyhj.fsf@news-spur.riddles.org.uk 2017-03-26 23:20:54 -04:00			`/*`
			`* knapsack.h`
			`*`
Update copyright for 2025 Backpatch-through: 13 2025-01-01 11:21:55 -05:00			`* Copyright (c) 2017-2025, PostgreSQL Global Development Group`
Support hashed aggregation with grouping sets. This extends the Aggregate node with two new features: HashAggregate can now run multiple hashtables concurrently, and a new strategy MixedAggregate populates hashtables while doing sorted grouping. The planner will now attempt to save as many sorts as possible when planning grouping sets queries, while not exceeding work_mem for the estimated combined sizes of all hashtables used. No SQL-level changes are required. There should be no user-visible impact other than the new EXPLAIN output and possible changes to result ordering when ORDER BY was not used (which affected a few regression tests). The enable_hashagg option is respected. Author: Andrew Gierth Reviewers: Mark Dilger, Andres Freund Discussion: https://postgr.es/m/87vatszyhj.fsf@news-spur.riddles.org.uk 2017-03-26 23:20:54 -04:00			`*`
			`* src/include/lib/knapsack.h`
			`*/`
			`#ifndef KNAPSACK_H`
			`#define KNAPSACK_H`

			`#include "nodes/bitmapset.h"`

			`extern Bitmapset *DiscreteKnapsack(int max_weight, int num_items,`
			`int item_weights, double item_values);`

			`#endif /* KNAPSACK_H */`