Package io.trino.cost

Class PlanNodeStatsEstimateMath

java.lang.Object

io.trino.cost.PlanNodeStatsEstimateMath

public final class PlanNodeStatsEstimateMath
extends Object

Method Summary

Modifier and Type	Method	Description
static PlanNodeStatsEstimate	addStatsAndCollapseDistinctValues(PlanNodeStatsEstimate left, PlanNodeStatsEstimate right)
static PlanNodeStatsEstimate	addStatsAndMaxDistinctValues(PlanNodeStatsEstimate left, PlanNodeStatsEstimate right)
static PlanNodeStatsEstimate	addStatsAndSumDistinctValues(PlanNodeStatsEstimate left, PlanNodeStatsEstimate right)
static PlanNodeStatsEstimate	capStats(PlanNodeStatsEstimate stats, PlanNodeStatsEstimate cap)
static double	estimateCorrelatedConjunctionRowCount(PlanNodeStatsEstimate input, List<PlanNodeStatsEstimate> estimates, double independenceFactor)
static double	getFirstKnownOutputSizeInBytes(PlanNode node, Lookup lookup, StatsProvider statsProvider)	Recursively looks for the first source node with a known estimate and uses that to return an approximate output size.
static double	getSourceTablesSizeInBytes(PlanNode node, Lookup lookup, StatsProvider statsProvider)
static Map<Symbol,SymbolStatsEstimate>	intersectCorrelatedStats(List<PlanNodeStatsEstimate> estimates)
static PlanNodeStatsEstimate	subtractSubsetStats(PlanNodeStatsEstimate superset, PlanNodeStatsEstimate subset)	Subtracts subset stats from supersets stats.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

subtractSubsetStats

public static PlanNodeStatsEstimate subtractSubsetStats(PlanNodeStatsEstimate superset,
 PlanNodeStatsEstimate subset)

Subtracts subset stats from supersets stats. It is assumed that each NDV from subset has a matching NDV in superset.

capStats

public static PlanNodeStatsEstimate capStats(PlanNodeStatsEstimate stats,
 PlanNodeStatsEstimate cap)

intersectCorrelatedStats

public static Map<Symbol,SymbolStatsEstimate> intersectCorrelatedStats(List<PlanNodeStatsEstimate> estimates)

estimateCorrelatedConjunctionRowCount

public static double estimateCorrelatedConjunctionRowCount(PlanNodeStatsEstimate input,
 List<PlanNodeStatsEstimate> estimates,
 double independenceFactor)

getFirstKnownOutputSizeInBytes

public static double getFirstKnownOutputSizeInBytes(PlanNode node,
 Lookup lookup,
 StatsProvider statsProvider)

Recursively looks for the first source node with a known estimate and uses that to return an approximate output size. Returns NaN if an un-estimated expanding node (Join or Unnest) is encountered. The amount of reduction in size from un-estimated non-expanding nodes (e.g. an un-estimated filter or aggregation) is not accounted here. We make use of the first available estimate and make decision about flipping join sides only if we find a large difference in output size of both sides.

getSourceTablesSizeInBytes

public static double getSourceTablesSizeInBytes(PlanNode node,
 Lookup lookup,
 StatsProvider statsProvider)

addStatsAndSumDistinctValues

public static PlanNodeStatsEstimate addStatsAndSumDistinctValues(PlanNodeStatsEstimate left,
 PlanNodeStatsEstimate right)

addStatsAndMaxDistinctValues

public static PlanNodeStatsEstimate addStatsAndMaxDistinctValues(PlanNodeStatsEstimate left,
 PlanNodeStatsEstimate right)

addStatsAndCollapseDistinctValues

public static PlanNodeStatsEstimate addStatsAndCollapseDistinctValues(PlanNodeStatsEstimate left,
 PlanNodeStatsEstimate right)