org.tikv.common.statistics

类 Bucket

java.lang.Object

org.tikv.common.statistics.Bucket

所有已实现的接口:

Comparable<Bucket>

public class Bucket
extends Object
implements Comparable<Bucket>

Bucket is histogram element.

Bucket bound is the smallest and greatest values stored in the bucket. The lower and upper bound are stored in bucket as lowerBound and upperBound.

A bucket count is the number of items stored in all previous buckets and the current bucket. Bucket counts are always in increasing order.

A bucket repeat is the number of repeats of the greatest bucket value, it can be used to find popular values.

Note that lowerBound and upperBound keys should be 'comparable objects', and these bounds are encoded as `binary` type in TiDB. Intuitively, you should also use Keys encoded as binary format to do comparison in row count estimation.

字段概要

字段

限定符和类型	字段和说明
long	count

构造器概要

构造器

构造器和说明
Bucket(Key upperBound) used for binary search only
Bucket(long count, long repeats, Key lowerBound, Key upperBound)

方法概要

限定符和类型	方法和说明
int	compareTo(Bucket b)
long	getCount()
Key	getLowerBound()
long	getRepeats()
Key	getUpperBound()
void	setCount(long count)
void	setLowerBound(Key lowerBound)
void	setRepeats(long repeats)
void	setUpperBound(Key upperBound)
String	toString()

从类继承的方法 java.lang.Object

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

字段详细资料

count

public long count

构造器详细资料

Bucket

public Bucket(long count,
              long repeats,
              Key lowerBound,
              Key upperBound)

Bucket

public Bucket(Key upperBound)

used for binary search only

方法详细资料

compareTo

public int compareTo(Bucket b)

指定者:

compareTo 在接口中 Comparable<Bucket>

getCount

public long getCount()

setCount

public void setCount(long count)

getRepeats

public long getRepeats()

setRepeats

public void setRepeats(long repeats)

getLowerBound

public Key getLowerBound()

setLowerBound

public void setLowerBound(Key lowerBound)

getUpperBound

public Key getUpperBound()

setUpperBound

public void setUpperBound(Key upperBound)

toString

public String toString()

覆盖:

toString 在类中 Object