com.dynamic.sql.core.column.function.windows.aggregate

Class Variance

java.lang.Object

com.dynamic.sql.core.column.function.AbstractColumFunction

com.dynamic.sql.core.column.function.ColumnFunctionDecorator

com.dynamic.sql.core.column.function.windows.aggregate.Variance

All Implemented Interfaces:

ColumnArithmetic, ColumFunction, AggregateFunction, WindowsFunction, Serializable

public class Variance
extends ColumnFunctionDecorator
implements AggregateFunction, WindowsFunction

计算指定列的方差。

例如：VARIANCE(salary) 返回薪资列的方差。

See Also:

Serialized Form

Field Summary

Fields inherited from class com.dynamic.sql.core.column.function.ColumnFunctionDecorator

parameterBinder, value

Fields inherited from class com.dynamic.sql.core.column.function.AbstractColumFunction

aliasTableMap, dataSourceName, delegateFunction, sqlDialect, version

Constructor Summary

Constructors

Constructor and Description
Variance(AbstractColumFunction delegateFunction)
Variance(FieldFn<T,F> fn)
Variance(String tableAlias, FieldFn<T,F> fn)

Method Summary

Modifier and Type	Method and Description
String	getFunctionToString(SqlDialect sqlDialect, Version version)

Methods inherited from class com.dynamic.sql.core.column.function.ColumnFunctionDecorator

appendArithmeticSql, getOriginColumnFn, getParameterBinder, getTableAlias

Methods inherited from class com.dynamic.sql.core.column.function.AbstractColumFunction

add, add, add, add, divide, divide, divide, divide, getAliasTableMap, getArithmetic, getDataSourceName, getDelegateFunction, multiply, multiply, multiply, multiply, setAliasTableMap, setArithmetic, setDataSourceName, setSqlDialect, setVersion, subtract, subtract, subtract, subtract

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.dynamic.sql.core.column.function.ColumFunction

getOriginColumnFn, getParameterBinder, getTableAlias, setTableAlias

Constructor Detail

Variance

public Variance(AbstractColumFunction delegateFunction)

Variance

public Variance(FieldFn<T,F> fn)

Variance

public Variance(String tableAlias,
                FieldFn<T,F> fn)

Method Detail

getFunctionToString

public String getFunctionToString(SqlDialect sqlDialect,
                                  Version version)
                           throws UnsupportedOperationException

Specified by:

getFunctionToString in interface ColumFunction

Throws:

UnsupportedOperationException