Package com.orientechnologies.orient.core.sql.functions.stat

Class OSQLFunctionStandardDeviation

java.lang.Object

com.orientechnologies.orient.core.sql.functions.OSQLFunctionAbstract

com.orientechnologies.orient.core.sql.functions.stat.OSQLFunctionVariance

com.orientechnologies.orient.core.sql.functions.stat.OSQLFunctionStandardDeviation

All Implemented Interfaces:

OSQLFunction

public class OSQLFunctionStandardDeviation
extends OSQLFunctionVariance

Compute the standard deviation for a given field.

Author:

Fabrizio Fortino

Field Summary

Fields

Modifier and Type	Field	Description
static final String	NAME

Fields inherited from class com.orientechnologies.orient.core.sql.functions.OSQLFunctionAbstract

maxParams, minParams, name

Constructor Summary

Constructors

Constructor	Description
OSQLFunctionStandardDeviation()

Method Summary

Modifier and Type	Method	Description
Object	getResult(OCommandContext ctx)	Only called when function aggregates results after all records have been passed to the function.
String	getSyntax()	Returns a convenient SQL String representation of the function.
Object	mergeDistributedResult(List<Object> resultsToMerge)	This method correspond to distributed query execution

Methods inherited from class com.orientechnologies.orient.core.sql.functions.stat.OSQLFunctionVariance

aggregateResults, execute

Methods inherited from class com.orientechnologies.orient.core.sql.functions.OSQLFunctionAbstract

config, filterResult, getDatabase, getDistributedStorageId, getMaxParams, getMinParams, getName, getSingleItem, getSingleProperty, returnDistributedResult, setResult, shouldMergeDistributedResult, toString

Methods inherited from class java.lang.Object

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

Field Details

NAME

public static final String NAME

See Also:

• Constant Field Values

Constructor Details

OSQLFunctionStandardDeviation

public OSQLFunctionStandardDeviation()

Method Details

getResult

public Object getResult(OCommandContext ctx)

Description copied from interface: OSQLFunction

Only called when function aggregates results after all records have been passed to the function.

Specified by:

getResult in interface OSQLFunction

Overrides:

getResult in class OSQLFunctionVariance

Parameters:

ctx - TODO

Returns:

Aggregation result

mergeDistributedResult

public Object mergeDistributedResult(List<Object> resultsToMerge)

Description copied from interface: OSQLFunction

This method correspond to distributed query execution

Specified by:

mergeDistributedResult in interface OSQLFunction

Overrides:

mergeDistributedResult in class OSQLFunctionVariance

Parameters:

resultsToMerge - is the results that comes from different nodes

Returns:

is the valid merged result

getSyntax

public String getSyntax()

Description copied from interface: OSQLFunction

Returns a convenient SQL String representation of the function.

Example :

  myFunction( param1, param2, [optionalParam3])
 

This text will be used in exception messages.

Specified by:

getSyntax in interface OSQLFunction

Overrides:

getSyntax in class OSQLFunctionVariance

Returns:

String , never null.