org.apache.spark.sql.connector.expressions

Interface Expression

All Known Subinterfaces:

AggregateFunc, Literal<T>, NamedReference, RewritableTransform, SortOrder, Transform

All Known Implementing Classes:

AlwaysFalse, AlwaysTrue, And, Avg, Cast, Count, CountStar, org.apache.spark.sql.internal.connector.ExpressionWithToString, Extract, GeneralAggregateFunc, GeneralScalarExpression, Max, Min, Not, Or, Predicate, Sum, UserDefinedAggregateFunc, UserDefinedScalarFunc

@Evolving
public interface Expression

Base class of the public logical expression API.

Since:

3.0.0

Field Summary

Fields

Modifier and Type	Field and Description
static Expression[]	EMPTY_EXPRESSION
static NamedReference[]	EMPTY_NAMED_REFERENCE `EMPTY_EXPRESSION` is only used as an input when the default `references` method builds the result array to avoid repeatedly allocating an empty array.

Method Summary

Modifier and Type	Method and Description
Expression[]	children() Returns an array of the children of this node.
default String	describe() Format the expression as a human readable SQL-like string.
default NamedReference[]	references() List of fields or columns that are referenced by this expression.

Field Detail

EMPTY_EXPRESSION

static final Expression[] EMPTY_EXPRESSION

EMPTY_NAMED_REFERENCE

static final NamedReference[] EMPTY_NAMED_REFERENCE

`EMPTY_EXPRESSION` is only used as an input when the default `references` method builds the result array to avoid repeatedly allocating an empty array.

Method Detail

describe

default String describe()

Format the expression as a human readable SQL-like string.

children

Expression[] children()

Returns an array of the children of this node. Children should not change.

references

default NamedReference[] references()

List of fields or columns that are referenced by this expression.