rewriteManip.h

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/*-------------------------------------------------------------------------
 *
 * rewriteManip.h
 *      Querytree manipulation subroutines for query rewriter.
 *
 *
 * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * src/include/rewrite/rewriteManip.h
 *
 *-------------------------------------------------------------------------
 */
#ifndef REWRITEMANIP_H
#define REWRITEMANIP_H

#include "nodes/parsenodes.h"


typedef struct replace_rte_variables_context replace_rte_variables_context;

typedef Node *(*replace_rte_variables_callback) (Var *var,
                                                 replace_rte_variables_context *context);

struct replace_rte_variables_context
{
    replace_rte_variables_callback callback;    /* callback function */
    void       *callback_arg;   /* context data for callback function */
    int         target_varno;   /* RTE index to search for */
    int         sublevels_up;   /* (current) nesting depth */
    bool        inserted_sublink;   /* have we inserted a SubLink? */
};

typedef enum ReplaceVarsNoMatchOption
{
    REPLACEVARS_REPORT_ERROR,   /* throw error if no match */
    REPLACEVARS_CHANGE_VARNO,   /* change the Var's varno, nothing else */
    REPLACEVARS_SUBSTITUTE_NULL /* replace with a NULL Const */
} ReplaceVarsNoMatchOption;


extern void OffsetVarNodes(Node *node, int offset, int sublevels_up);
extern void ChangeVarNodes(Node *node, int old_varno, int new_varno,
                           int sublevels_up);
extern void IncrementVarSublevelsUp(Node *node, int delta_sublevels_up,
                                    int min_sublevels_up);
extern void IncrementVarSublevelsUp_rtable(List *rtable,
                                           int delta_sublevels_up, int min_sublevels_up);

extern bool rangeTableEntry_used(Node *node, int rt_index,
                                 int sublevels_up);

extern Query *getInsertSelectQuery(Query *parsetree, Query ***subquery_ptr);

extern void AddQual(Query *parsetree, Node *qual);
extern void AddInvertedQual(Query *parsetree, Node *qual);

extern bool contain_aggs_of_level(Node *node, int levelsup);
extern int  locate_agg_of_level(Node *node, int levelsup);
extern bool contain_windowfuncs(Node *node);
extern int  locate_windowfunc(Node *node);
extern bool checkExprHasSubLink(Node *node);

extern Node *replace_rte_variables(Node *node,
                                   int target_varno, int sublevels_up,
                                   replace_rte_variables_callback callback,
                                   void *callback_arg,
                                   bool *outer_hasSubLinks);
extern Node *replace_rte_variables_mutator(Node *node,
                                           replace_rte_variables_context *context);

extern Node *map_variable_attnos(Node *node,
                                 int target_varno, int sublevels_up,
                                 const AttrNumber *attno_map, int map_length,
                                 Oid to_rowtype, bool *found_whole_row);

extern Node *ReplaceVarsFromTargetList(Node *node,
                                       int target_varno, int sublevels_up,
                                       RangeTblEntry *target_rte,
                                       List *targetlist,
                                       ReplaceVarsNoMatchOption nomatch_option,
                                       int nomatch_varno,
                                       bool *outer_hasSubLinks);

#endif                          /* REWRITEMANIP_H */