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45 lines
1.1 KiB
C
45 lines
1.1 KiB
C
/*-------------------------------------------------------------------------
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*
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* blcost.c
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* Cost estimate function for bloom indexes.
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*
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* Copyright (c) 2016-2021, PostgreSQL Global Development Group
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*
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* IDENTIFICATION
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* contrib/bloom/blcost.c
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*
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*-------------------------------------------------------------------------
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*/
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#include "postgres.h"
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#include "bloom.h"
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#include "fmgr.h"
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#include "utils/selfuncs.h"
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/*
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* Estimate cost of bloom index scan.
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*/
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void
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blcostestimate(PlannerInfo *root, IndexPath *path, double loop_count,
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Cost *indexStartupCost, Cost *indexTotalCost,
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Selectivity *indexSelectivity, double *indexCorrelation,
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double *indexPages)
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{
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IndexOptInfo *index = path->indexinfo;
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GenericCosts costs;
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MemSet(&costs, 0, sizeof(costs));
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/* We have to visit all index tuples anyway */
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costs.numIndexTuples = index->tuples;
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/* Use generic estimate */
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genericcostestimate(root, path, loop_count, &costs);
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*indexStartupCost = costs.indexStartupCost;
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*indexTotalCost = costs.indexTotalCost;
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*indexSelectivity = costs.indexSelectivity;
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*indexCorrelation = costs.indexCorrelation;
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*indexPages = costs.numIndexPages;
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}
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