Package org.elasticsearch.xpack.esql.core.expression

Class Expressions

java.lang.Object

org.elasticsearch.xpack.esql.core.expression.Expressions

public final class Expressions
extends Object

Method Summary

Modifier and Type	Method	Description
static List<Tuple<Attribute,Expression>>	aliases(List<? extends NamedExpression> named)
static boolean	anyMatch(List<? extends Expression> exps, Predicate<? super Expression> predicate)
static List<Attribute>	asAttributes(List<? extends NamedExpression> named)
static Attribute	attribute(Expression e)
static List<Expression>	canonicalize(List<? extends Expression> exps)
static boolean	equalsAsAttribute(Expression left, Expression right)
static List<Object>	fold(FoldContext ctx, List<? extends Expression> exps)
static boolean	foldable(List<? extends Expression> exps)
static String	id(Expression e)
static boolean	isGuaranteedNull(Expression e)	Is this Expression guaranteed to have only the null value.
static boolean	isPresent(NamedExpression e)
static boolean	listSemanticEqualsIgnoreOrder(List<Expression> left, List<Expression> right)
static boolean	match(List<? extends Expression> exps, Predicate<? super Expression> predicate)
static String	name(Expression e)
static List<String>	names(Collection<? extends Expression> e)
static Nullability	nullable(List<? extends Expression> exps)	Return the logical AND of a list of Nullability
static AttributeSet	references(List<? extends Expression> exps)
static List<Attribute>	toReferenceAttributesPreservingIds(List<? extends NamedExpression> named, List<Attribute> existingOutput)	Converts named expressions to ReferenceAttributes, preserving NameIds for attributes whose name matches one in existingOutput.

Methods inherited from class java.lang.Object

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

Method Details

asAttributes

public static List<Attribute> asAttributes(List<? extends NamedExpression> named)

toReferenceAttributesPreservingIds

public static List<Attribute> toReferenceAttributesPreservingIds(List<? extends NamedExpression> named,
 List<Attribute> existingOutput)

Converts named expressions to ReferenceAttributes, preserving NameIds for attributes whose name matches one in existingOutput. Genuinely new attributes get fresh NameIds.

Exceptions to the ReferenceAttribute conversion:

• A FieldAttribute backed by a TypeConflictedField (ambiguous type across indices) is converted to an UnsupportedAttribute via FieldAttribute.flagTypeConflicts(), so the analyzer can surface a clear user-facing error. Exception: a two-legged PUNK (TypeConflictedField.isSingleTypePotentiallyUnmapped()) keeps its single mapped type on the ReferenceAttribute so it surfaces through a Fork/UnionAll output.
• An ExternalMetadataAttribute is rebuilt as the same subtype with the preserved id. The "virtual column" identity must survive operators that re-class their output (e.g. Fork.refreshedOutput) because downstream rules such as Analyzer.planWithoutSyntheticAttributes (which strips _file.* from the default top-level projection) and the predicate-pushdown helpers (PushdownPredicates#isVirtualColumn) test this subtype to decide whether an attribute is a virtual column or a real data column. Erasing the type would silently leak _file.* into default output and would also re-enable predicate pushdown on virtual columns past a Fork.

anyMatch

public static boolean anyMatch(List<? extends Expression> exps,
 Predicate<? super Expression> predicate)

match

public static boolean match(List<? extends Expression> exps,
 Predicate<? super Expression> predicate)

nullable

public static Nullability nullable(List<? extends Expression> exps)

Return the logical AND of a list of Nullability

  UNKNOWN AND TRUE/FALSE/UNKNOWN = UNKNOWN
  FALSE AND FALSE = FALSE
  TRUE AND FALSE/TRUE = TRUE
 

canonicalize

public static List<Expression> canonicalize(List<? extends Expression> exps)

foldable

public static boolean foldable(List<? extends Expression> exps)

fold

public static List<Object> fold(FoldContext ctx,
 List<? extends Expression> exps)

references

public static AttributeSet references(List<? extends Expression> exps)

name

public static String name(Expression e)

isGuaranteedNull

public static boolean isGuaranteedNull(Expression e)

Is this Expression guaranteed to have only the null value. Expressions that Expression.fold(org.elasticsearch.xpack.esql.core.expression.FoldContext) to null may return false here, but should eventually be folded into a Literal containing null which will return true from here.

names

public static List<String> names(Collection<? extends Expression> e)

attribute

public static Attribute attribute(Expression e)

isPresent

public static boolean isPresent(NamedExpression e)

equalsAsAttribute

public static boolean equalsAsAttribute(Expression left,
 Expression right)

listSemanticEqualsIgnoreOrder

public static boolean listSemanticEqualsIgnoreOrder(List<Expression> left,
 List<Expression> right)

aliases

public static List<Tuple<Attribute,Expression>> aliases(List<? extends NamedExpression> named)

id

public static String id(Expression e)