MySQL 9.5.0
Source Code Documentation
HashJoinCost Class Referencefinal

This class represents the cost of a hash join (excluding the cost of sub-paths). More...

#include <cost_model.h>

Public Member Functions

 HashJoinCost (THD *thd, const HashJoinMetrics &metrics)
 
double spill_to_disk_probability () const
 
double init_cost () const
 
double cost () const
 

Private Attributes

double m_spill_to_disk_probability
 The probability (range [0.0, 1.0]) of needing spill to disk. More...
 
double m_init_cost
 The cost of preparing to produce the first result row. More...
 
double m_cost
 The cost of the hash join. More...
 

Detailed Description

This class represents the cost of a hash join (excluding the cost of sub-paths).

Constructor & Destructor Documentation

◆ HashJoinCost()

HashJoinCost::HashJoinCost ( THD thd,
const HashJoinMetrics metrics 
)

Member Function Documentation

◆ cost()

double HashJoinCost::cost ( ) const
inline

◆ init_cost()

double HashJoinCost::init_cost ( ) const
inline

◆ spill_to_disk_probability()

double HashJoinCost::spill_to_disk_probability ( ) const
inline

Member Data Documentation

◆ m_cost

double HashJoinCost::m_cost
private

The cost of the hash join.

◆ m_init_cost

double HashJoinCost::m_init_cost
private

The cost of preparing to produce the first result row.

◆ m_spill_to_disk_probability

double HashJoinCost::m_spill_to_disk_probability
private

The probability (range [0.0, 1.0]) of needing spill to disk.


The documentation for this class was generated from the following files: