Package org.apache.qpid.server.query.engine.parsing.expression.set

Class IntersectExpression<T>

java.lang.Object

org.apache.qpid.server.query.engine.parsing.expression.AbstractExpressionNode<T,R>

org.apache.qpid.server.query.engine.parsing.expression.set.AbstractSetExpression<T,java.util.stream.Stream<java.util.Map<java.lang.String,java.lang.Object>>>

org.apache.qpid.server.query.engine.parsing.expression.set.IntersectExpression<T>

Type Parameters:

T - Input parameter type

All Implemented Interfaces:

java.util.function.Function<T,java.util.stream.Stream<java.util.Map<java.lang.String,java.lang.Object>>>, Expression<T,java.util.stream.Stream<java.util.Map<java.lang.String,java.lang.Object>>>, ExpressionNode<T,java.util.stream.Stream<java.util.Map<java.lang.String,java.lang.Object>>>, SetExpression<T,java.util.stream.Stream<java.util.Map<java.lang.String,java.lang.Object>>>

public class IntersectExpression<T>
extends AbstractSetExpression<T,java.util.stream.Stream<java.util.Map<java.lang.String,java.lang.Object>>>

Set INTERSECT expression is used to retain the results of right SELECT statement present in the results of left SELECT statement. Every SELECT statement within INTERSECT must have the same number of columns. The INTERSECT operator selects all values by default. To eliminate duplicates, INTERSECT DISTINCT should be used.

Field Summary

Fields inherited from class org.apache.qpid.server.query.engine.parsing.expression.set.AbstractSetExpression

_distinct

Fields inherited from class org.apache.qpid.server.query.engine.parsing.expression.AbstractExpressionNode

_metadata

Constructor Summary

Constructors

Constructor	Description
IntersectExpression(boolean distinct, ExpressionNode<T,java.util.stream.Stream<java.util.Map<java.lang.String,java.lang.Object>>> left, ExpressionNode<T,java.util.stream.Stream<java.util.Map<java.lang.String,java.lang.Object>>> right)	Constructor initializes children expression list

Method Summary

Modifier and Type	Method	Description
java.util.stream.Stream<java.util.Map<java.lang.String,java.lang.Object>>	apply(T value)	Performs INTERSECT operation on both set expressions

Methods inherited from class org.apache.qpid.server.query.engine.parsing.expression.set.AbstractSetExpression

getProjections, getSelections

Methods inherited from class org.apache.qpid.server.query.engine.parsing.expression.AbstractExpressionNode

containsAggregation, ctx, evaluateChild, getAggregations, getAlias, getChild, getChildren, getParent, isAccessor, isInstantlyEvaluable, setAlias, setParent, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.qpid.server.query.engine.parsing.expression.Expression

andThen

Methods inherited from interface org.apache.qpid.server.query.engine.parsing.expression.ExpressionNode

containsAggregation, getAggregations, getAlias, getChildren, getParent, isAccessor, isInstantlyEvaluable, setAlias, setParent

Methods inherited from interface java.util.function.Function

andThen, compose

Constructor Detail

IntersectExpression

public IntersectExpression(boolean distinct,
                           ExpressionNode<T,java.util.stream.Stream<java.util.Map<java.lang.String,java.lang.Object>>> left,
                           ExpressionNode<T,java.util.stream.Stream<java.util.Map<java.lang.String,java.lang.Object>>> right)

Constructor initializes children expression list

Parameters:

distinct - Distinct flag

left - Left expression

right - Right expression

Method Detail

apply

public java.util.stream.Stream<java.util.Map<java.lang.String,java.lang.Object>> apply(T value)

Performs INTERSECT operation on both set expressions

Parameters:

value - Object to handle

Returns:

Stream combining entities from both expressions