EstimationUtils

EstimationUtils is…​FIXME

getOutputSize Method

getOutputSize(
  attributes: Seq[Attribute],
  outputRowCount: BigInt,
  attrStats: AttributeMap[ColumnStat] = AttributeMap(Nil)): BigInt

getOutputSize…​FIXME

Note
 getOutputSize is used when…​FIXME

nullColumnStat Method

nullColumnStat(dataType: DataType, rowCount: BigInt): ColumnStat

nullColumnStat…​FIXME

Note
 nullColumnStat is used exclusively when JoinEstimation is requested to estimateInnerOuterJoin for LeftOuter and RightOuter joins.

Checking Availability of Row Count Statistic — rowCountsExist Method

rowCountsExist(plans: LogicalPlan*): Boolean

rowCountsExist is positive (i.e. true) when every logical plan (in the input plans) has estimated number of rows (aka row count) statistic computed.

Otherwise, rowCountsExist is negative (i.e. false).

Note
 rowCountsExist uses LogicalPlanStats to access the estimated statistics and query hints of a logical plan.
Note

rowCountsExist is used when:

results matching ""

    No results matching ""