Package org.elasticsearch.xpack.esql.plan.logical.promql.selector

Class InstantSelector

java.lang.Object

org.elasticsearch.xpack.esql.core.tree.Node<LogicalPlan>

org.elasticsearch.xpack.esql.plan.QueryPlan<LogicalPlan>

org.elasticsearch.xpack.esql.plan.logical.LogicalPlan

org.elasticsearch.xpack.esql.plan.logical.UnaryPlan

org.elasticsearch.xpack.esql.plan.logical.promql.selector.Selector

org.elasticsearch.xpack.esql.plan.logical.promql.selector.InstantSelector

All Implemented Interfaces:

NamedWriteable, Writeable, Resolvable, PromqlPlan

public final class InstantSelector
extends Selector

Represents a PromQL instant vector selector.

An instant vector selects time series based on metric name and label matchers, returning the most recent sample at the evaluation timestamp. This corresponds to PromQL syntax:

 metric_name{label="value"} offset 5m @ timestamp
 

Examples:

 http_requests_total
 cpu_usage{host="web-1"}
 memory_used{env=~"prod.*"} offset 10m
 up{job="prometheus"} @ 1609746000
 

The instant vector selects a single sample per matching time series at the evaluation time (with optional offset/@ modifiers), representing the current state.

Conceptually an instant selector is a range selector with a null range.

Nested Class Summary

Nested classes/interfaces inherited from class org.elasticsearch.xpack.esql.plan.logical.LogicalPlan

LogicalPlan.Stage

Nested classes/interfaces inherited from class org.elasticsearch.xpack.esql.core.tree.Node

Node.NodeStringFormat

Nested classes/interfaces inherited from interface org.elasticsearch.common.io.stream.Writeable

Writeable.Reader<V>, Writeable.Writer<V>

Field Summary

Fields inherited from class org.elasticsearch.xpack.esql.plan.logical.promql.selector.Selector

output

Fields inherited from class org.elasticsearch.xpack.esql.core.tree.Node

TO_STRING_MAX_LINES, TO_STRING_MAX_WIDTH

Constructor Summary

Constructors

Constructor	Description
InstantSelector(Source source, Expression series, List<Expression> labels, LabelMatchers labelMatchers, Evaluation evaluation)
InstantSelector(Source source, LogicalPlan child, Expression series, List<Expression> labels, LabelMatchers labelMatchers, Evaluation evaluation)

Method Summary

Modifier and Type	Method	Description
boolean	equals(Object o)
int	hashCode()
protected NodeInfo<InstantSelector>	info()	Normally, you want to use one of the static create methods to implement this.
List<Attribute>	output()	The ordered list of attributes (i.e.
InstantSelector	replaceChild(LogicalPlan newChild)
PromqlDataType	returnType()	The PromQL return type of this plan node.

Methods inherited from class org.elasticsearch.xpack.esql.plan.logical.promql.selector.Selector

evaluation, expressionsResolved, getWriteableName, labelMatchers, labels, series, writeTo

Methods inherited from class org.elasticsearch.xpack.esql.plan.logical.UnaryPlan

child, inputSet, outputSet, replaceChildren

Methods inherited from class org.elasticsearch.xpack.esql.plan.logical.LogicalPlan

analyzed, childrenResolved, optimized, preAnalyzed, preOptimized, resolved, setAnalyzed, setOptimized, setPreAnalyzed, setPreOptimized

Methods inherited from class org.elasticsearch.xpack.esql.plan.QueryPlan

computeExpressions, computeReferences, expressions, forEachExpression, forEachExpression, forEachExpressionDown, forEachExpressionUp, references, transformExpressionsDown, transformExpressionsDown, transformExpressionsOnly, transformExpressionsOnly, transformExpressionsOnlyUp, transformExpressionsUp, transformExpressionsUp

Methods inherited from class org.elasticsearch.xpack.esql.core.tree.Node

allMatch, anyMatch, children, collect, collect, collect, collectFirstChildren, collectLeaves, doCollectFirst, forEachDown, forEachDown, forEachDownMayReturnEarly, forEachProperty, forEachPropertyDown, forEachPropertyOnly, forEachPropertyUp, forEachUp, forEachUp, nodeName, nodeProperties, nodeString, nodeString, propertiesToString, replaceChildrenSameSize, source, sourceLocation, sourceText, toString, toString, transformChildren, transformChildren, transformDown, transformDown, transformDown, transformDown, transformDownSkipBranch, transformNodeProps, transformPropertiesDown, transformPropertiesOnly, transformPropertiesUp, transformUp, transformUp, transformUp

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Details

InstantSelector

public InstantSelector(Source source,
 Expression series,
 List<Expression> labels,
 LabelMatchers labelMatchers,
 Evaluation evaluation)

InstantSelector

public InstantSelector(Source source,
 LogicalPlan child,
 Expression series,
 List<Expression> labels,
 LabelMatchers labelMatchers,
 Evaluation evaluation)

Method Details

info

protected NodeInfo<InstantSelector> info()

Description copied from class: Node

Normally, you want to use one of the static create methods to implement this.

For QueryPlans, it is very important that the properties contain all of the expressions and references relevant to this node, and that all the properties are used in the provided constructor; otherwise query plan transformations like QueryPlan#transformExpressionsOnly(Function) will not have an effect.

Specified by:

info in class Node<LogicalPlan>

replaceChild

public InstantSelector replaceChild(LogicalPlan newChild)

Specified by:

replaceChild in class UnaryPlan

equals

public boolean equals(Object o)

Overrides:

equals in class Selector

hashCode

public int hashCode()

Overrides:

hashCode in class Selector

output

public List<Attribute> output()

Description copied from class: QueryPlan

The ordered list of attributes (i.e. columns) this plan produces when executed. Must be called only on resolved plans, otherwise may throw an exception or return wrong results.

Specified by:

output in interface PromqlPlan

Overrides:

output in class UnaryPlan

returnType

public PromqlDataType returnType()

Description copied from interface: PromqlPlan

The PromQL return type of this plan node.