org.apache.calcite.rel.metadata

Interface BuiltInMetadata.PercentageOriginalRows

All Superinterfaces:

Metadata

Enclosing class:

BuiltInMetadata

public static interface BuiltInMetadata.PercentageOriginalRows
extends Metadata

Metadata about the proportion of original rows that remain in a relational expression.

Method Summary

Methods

Modifier and Type	Method and Description
Double	getPercentageOriginalRows() Estimates the percentage of the number of rows actually produced by a relational expression out of the number of rows it would produce if all single-table filter conditions were removed.

Methods inherited from interface org.apache.calcite.rel.metadata.Metadata

rel

Method Detail

getPercentageOriginalRows

Double getPercentageOriginalRows()

Estimates the percentage of the number of rows actually produced by a relational expression out of the number of rows it would produce if all single-table filter conditions were removed.

Returns:

estimated percentage (between 0.0 and 1.0), or null if no reliable estimate can be determined