text: /*-------------------------------------------------------------------------
   *
   * clauses.h
   *	  prototypes for clauses.c.
   *
   *
   * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
   * Portions Copyright (c) 1994, Regents of the University of California
   *
   * src/include/optimizer/clauses.h
   *
   *-------------------------------------------------------------------------
   */
  #ifndef CLAUSES_H
  #define CLAUSES_H
  
  #include "access/htup.h"
  #include "nodes/pathnodes.h"
  
  typedef struct
  {
  	int			numWindowFuncs; /* total number of WindowFuncs found */
  	Index		maxWinRef;		/* windowFuncs[] is indexed 0 .. maxWinRef */
  	List	  **windowFuncs;	/* lists of WindowFuncs for each winref */
  } WindowFuncLists;
  
  extern bool contain_agg_clause(Node *clause);
  extern void get_agg_clause_costs(PlannerInfo *root, Node *clause,
  								 AggSplit aggsplit, AggClauseCosts *costs);
  
  extern bool contain_window_function(Node *clause);
  extern WindowFuncLists *find_window_functions(Node *clause, Index maxWinRef);
  
  extern double expression_returns_set_rows(PlannerInfo *root, Node *clause);
  
  extern bool contain_subplans(Node *clause);
  
  extern char max_parallel_hazard(Query *parse);
  extern bool is_parallel_safe(PlannerInfo *root, Node *node);
  extern bool contain_nonstrict_functions(Node *clause);
  extern bool contain_leaked_vars(Node *clause);
  
  extern Relids find_nonnullable_rels(Node *clause);
  extern List *find_nonnullable_vars(Node *clause);
  extern List *find_forced_null_vars(Node *clause);
  extern Var *find_forced_null_var(Node *clause);
  
  extern bool is_pseudo_constant_clause(Node *clause);
  extern bool is_pseudo_constant_clause_relids(Node *clause, Relids relids);
  
  extern int	NumRelids(Node *clause);
  
  extern void CommuteOpExpr(OpExpr *clause);
  
  extern Query *inline_set_returning_function(PlannerInfo *root,
  											RangeTblEntry *rte);
  
  #endif							/* CLAUSES_H */
  