Package com.influxdb.query.dsl.functions

Class KeepFlux

java.lang.Object

com.influxdb.query.dsl.Flux

com.influxdb.query.dsl.functions.AbstractParametrizedFlux

com.influxdb.query.dsl.functions.KeepFlux

All Implemented Interfaces:

Expression, HasImports

public final class KeepFlux
extends AbstractParametrizedFlux

Keep is the inverse of drop. It will return a table containing only columns that are specified, ignoring all others. Only columns in the group key that are also specified in keep will be kept in the resulting group key. See SPEC.

Options

• columns - The list of columns that should be included in the resulting table. Cannot be used with fn. [array of strings]
• fn - The function which takes a column name as a parameter and returns a boolean indicating whether or not the column should be included in the resulting table. Cannot be used with columns. [function(column)]

Example

 Flux flux = Flux
     .from("telegraf")
     .keep(new String[]{"_time", "_value"});

 Flux flux = Flux
     .from("telegraf")
     .keep()
         .withFunction("column =~ /*inodes/");
 

Author:

Jakub Bednar (bednar@github) (02/08/2018 11:22)

Field Summary

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

functionsParameters, imports

Constructor Summary

Constructors

Constructor	Description
KeepFlux(Flux source)

Method Summary

Modifier and Type	Method	Description
void	collectImports(Set<String> collectedImports)	Collects all imports of the flux.
protected String	operatorName()
KeepFlux	withColumns(String[] columns)
KeepFlux	withColumns(Collection<String> columns)
KeepFlux	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

KeepFlux

public KeepFlux(@Nonnull
 Flux source)

Method Details

operatorName

@Nonnull
protected String operatorName()

Specified by:

operatorName in class AbstractParametrizedFlux

Returns:

name of function

withColumns

@Nonnull
public KeepFlux withColumns(@Nonnull
 String[] columns)

Parameters:

columns - The list of columns that should be included in the resulting table.

Returns:

this

withColumns

@Nonnull
public KeepFlux withColumns(@Nonnull
 Collection<String> columns)

Parameters:

columns - The list of columns that should be included in the resulting table.

Returns:

this

withFunction

@Nonnull
public KeepFlux withFunction(@Nonnull
 String function)

Parameters:

function - The function which takes a column name as a parameter and returns a boolean indicating whether or not the column should be included in the resulting table.

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