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/*-------------------------------------------------------------------------
*
* cost.h
* prototypes for costsize.c and clausesel.c.
*
*
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/optimizer/cost.h,v 1.62 2004-12-31 22:03:36 pgsql Exp $
*
*-------------------------------------------------------------------------
*/
#ifndef COST_H
#define COST_H
#include "nodes/plannodes.h"
#include "nodes/relation.h"
/* defaults for costsize.c's Cost parameters */
/* NB: cost-estimation code should use the variables, not these constants! */
/* If you change these, update backend/utils/misc/postgresql.sample.conf */
#define DEFAULT_EFFECTIVE_CACHE_SIZE 1000.0 /* measured in pages */
#define DEFAULT_RANDOM_PAGE_COST 4.0
#define DEFAULT_CPU_TUPLE_COST 0.01
#define DEFAULT_CPU_INDEX_TUPLE_COST 0.001
#define DEFAULT_CPU_OPERATOR_COST 0.0025
/*
* prototypes for costsize.c
* routines to compute costs and sizes
*/
/* parameter variables and flags */
extern double effective_cache_size;
extern double random_page_cost;
extern double cpu_tuple_cost;
extern DLLIMPORT double cpu_index_tuple_cost;
extern double cpu_operator_cost;
extern Cost disable_cost;
extern bool enable_seqscan;
extern bool enable_indexscan;
extern bool enable_tidscan;
extern bool enable_sort;
extern bool enable_hashagg;
extern bool enable_nestloop;
extern bool enable_mergejoin;
extern bool enable_hashjoin;
extern double clamp_row_est(double nrows);
extern void cost_seqscan(Path *path, Query *root,
RelOptInfo *baserel);
extern void cost_index(Path *path, Query *root,
RelOptInfo *baserel, IndexOptInfo *index,
List *indexQuals, bool is_injoin);
extern void cost_tidscan(Path *path, Query *root,
RelOptInfo *baserel, List *tideval);
extern void cost_subqueryscan(Path *path, RelOptInfo *baserel);
extern void cost_functionscan(Path *path, Query *root,
RelOptInfo *baserel);
extern void cost_sort(Path *path, Query *root,
List *pathkeys, Cost input_cost, double tuples, int width);
extern void cost_material(Path *path,
Cost input_cost, double tuples, int width);
extern void cost_agg(Path *path, Query *root,
AggStrategy aggstrategy, int numAggs,
int numGroupCols, double numGroups,
Cost input_startup_cost, Cost input_total_cost,
double input_tuples);
extern void cost_group(Path *path, Query *root,
int numGroupCols, double numGroups,
Cost input_startup_cost, Cost input_total_cost,
double input_tuples);
extern void cost_nestloop(NestPath *path, Query *root);
extern void cost_mergejoin(MergePath *path, Query *root);
extern void cost_hashjoin(HashPath *path, Query *root);
extern void cost_qual_eval(QualCost *cost, List *quals);
extern void set_baserel_size_estimates(Query *root, RelOptInfo *rel);
extern void set_joinrel_size_estimates(Query *root, RelOptInfo *rel,
RelOptInfo *outer_rel,
RelOptInfo *inner_rel,
JoinType jointype,
List *restrictlist);
extern void set_function_size_estimates(Query *root, RelOptInfo *rel);
/*
* prototypes for clausesel.c
* routines to compute clause selectivities
*/
extern Selectivity clauselist_selectivity(Query *root,
List *clauses,
int varRelid,
JoinType jointype);
extern Selectivity clause_selectivity(Query *root,
Node *clause,
int varRelid,
JoinType jointype);
#endif /* COST_H */
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