blcost.c

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/*-------------------------------------------------------------------------
 *
 * blcost.c
 *      Cost estimate function for bloom indexes.
 *
 * Copyright (c) 2016-2023, PostgreSQL Global Development Group
 *
 * IDENTIFICATION
 *    contrib/bloom/blcost.c
 *
 *-------------------------------------------------------------------------
 */
#include "postgres.h"
 
#include "bloom.h"
#include "fmgr.h"
#include "utils/selfuncs.h"
 
/*
 * Estimate cost of bloom index scan.
 */
void
blcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
               Cost *indexStartupCost, Cost *indexTotalCost,
               Selectivity *indexSelectivity, double *indexCorrelation,
               double *indexPages)
{
    IndexOptInfo *index = path->indexinfo;
    GenericCosts costs = {0};
 
    /* We have to visit all index tuples anyway */
    costs.numIndexTuples = index->tuples;
 
    /* Use generic estimate */
    genericcostestimate(root, path, loop_count, &costs);
 
    *indexStartupCost = costs.indexStartupCost;
    *indexTotalCost = costs.indexTotalCost;
    *indexSelectivity = costs.indexSelectivity;
    *indexCorrelation = costs.indexCorrelation;
    *indexPages = costs.numIndexPages;
}