Package com.influxdb.query.dsl.functions

Class MapFlux

java.lang.Object

com.influxdb.query.dsl.Flux

com.influxdb.query.dsl.functions.AbstractParametrizedFlux

com.influxdb.query.dsl.functions.MapFlux

All Implemented Interfaces:

Expression, HasImports

public final class MapFlux
extends AbstractParametrizedFlux

Applies a function to each row of the table. See SPEC.

Options

• fn - The function to apply to each row. The return value of the function may be a single value or an object. [function(record) value]

Example

 Restrictions restriction = Restrictions.and(
     Restrictions.measurement().equal("cpu"),
     Restrictions.field().equal("usage_system"),
     Restrictions.tag("service").equal("app-server")
 );

 // Square the value
 Flux flux = Flux
     .from("telegraf")
     .filter(restriction)
     .range(-12L, ChronoUnit.HOURS)
     .map("r._value * r._value");

 // Square the value and keep the original value
 Flux flux = Flux
     .from("telegraf")
     .filter(restriction)
     .range(-12L, ChronoUnit.HOURS)
     .map("{value: r._value, value2:r._value * r._value}");
 

Author:

Jakub Bednar (bednar@github) (17/07/2018 07:48)

Field Summary

Fields inherited from class com.influxdb.query.dsl.Flux

functionsParameters, imports

Constructor Summary

Constructors

Constructor	Description
MapFlux(Flux source)

Method Summary

Modifier and Type	Method	Description
void	collectImports(Set<String> collectedImports)	Collects all imports of the flux.
protected String	operatorName()
MapFlux	withFunction(String function)

Methods inherited from class com.influxdb.query.dsl.functions.AbstractParametrizedFlux

appendActual, beforeAppendOperatorName

Methods inherited from class com.influxdb.query.dsl.Flux

addImport, aggregateWindow, aggregateWindow, arrayFrom, arrayFrom, asVariable, columns, columns, count, count, covariance, covariance, covariance, covariance, covariance, covariance, covariance, covariance, covariance, cumulativeSum, cumulativeSum, cumulativeSum, derivative, derivative, difference, difference, difference, difference, difference, difference, distinct, distinct, drop, drop, drop, drop, duplicate, duplicate, elapsed, elapsed, elapsed, elapsed, expression, fill, fill, filter, filter, first, from, from, from, function, getImports, group, groupBy, groupBy, groupBy, groupExcept, groupExcept, groupExcept, integral, integral, interpolateLinear, interpolateLinear, join, join, keep, keep, keep, keep, last, last, limit, limit, limit, map, map, max, max, mean, mean, min, min, pivot, pivot, pivot, quantile, quantile, quantile, quantile, quantile, range, range, range, range, range, range, range, reduce, reduce, rename, rename, rename, sample, sample, sample, set, set, skew, skew, sort, sort, sort, sort, sort, sort, spread, spread, stddev, stddev, sum, sum, tail, tail, tail, timeShift, timeShift, timeShift, timeShift, to, to, to, to, to, to, to, to, toBool, toDuration, toFloat, toInt, toString, toString, toString, toStringConvert, toTime, toUInt, truncateTimeColumn, union, window, window, window, window, window, window, window, withFunction, withFunctionNamed, withPipedFunction, withPropertyNamed, withPropertyNamed, withPropertyValue, withPropertyValue, withPropertyValueEscaped, yield, yield

Methods inherited from class java.lang.Object

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

Constructor Details

MapFlux

public MapFlux(@Nonnull
 Flux source)

Method Details

operatorName

@Nonnull
protected String operatorName()

Specified by:

operatorName in class AbstractParametrizedFlux

Returns:

name of function

withFunction

@Nonnull
public MapFlux withFunction(@Nonnull
 String function)

Parameters:

function - The function for map row of table. Example: "r._value * r._value".

Returns:

this

collectImports

public void collectImports(@Nonnull
 Set<String> collectedImports)

Description copied from class: Flux

Collects all imports of the flux.

Overrides:

collectImports in class Flux

Parameters:

collectedImports - a set to be filled by the used imports