DelegatingLatticeStatisticProvider (Apache Calcite API)

java.lang.Object
- org.apache.calcite.materialize.DelegatingLatticeStatisticProvider

All Implemented Interfaces:

LatticeStatisticProvider
```
public class DelegatingLatticeStatisticProvider
extends java.lang.Object
implements LatticeStatisticProvider
```
Implementation of LatticeStatisticProvider that delegates to an underlying provider.

Nested Class Summary
- Nested classes/interfaces inherited from interface org.apache.calcite.materialize.LatticeStatisticProvider
  LatticeStatisticProvider.Factory

Field Summary

Fields
Modifier and Type Field Description

protected LatticeStatisticProvider provider

Constructor Summary

Constructors
Modifier Constructor Description

protected DelegatingLatticeStatisticProvider(LatticeStatisticProvider provider)
Creates a DelegatingLatticeStatisticProvider.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`double`	`cardinality(java.util.List<Lattice.Column> columns)`	Returns an estimate of the number of distinct values in a column or list of columns.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - provider
```
protected final LatticeStatisticProvider provider
```
- Constructor Detail
  - DelegatingLatticeStatisticProvider
```
protected DelegatingLatticeStatisticProvider(LatticeStatisticProvider provider)
```
    Creates a DelegatingLatticeStatisticProvider.
    
    Parameters:
    
    provider - Provider to which to delegate otherwise unhandled requests
- Method Detail
  - cardinality
```
public double cardinality(java.util.List<Lattice.Column> columns)
```
    Description copied from interface: LatticeStatisticProvider
    
    Returns an estimate of the number of distinct values in a column or list of columns.
    
    Specified by:
    
    cardinality in interface LatticeStatisticProvider