org.apache.calcite.rel.core

Class Intersect

java.lang.Object

org.apache.calcite.rel.AbstractRelNode

org.apache.calcite.rel.core.SetOp

org.apache.calcite.rel.core.Intersect

All Implemented Interfaces:

Cloneable, RelOptNode, RelNode

Direct Known Subclasses:

EnumerableIntersect, JdbcRules.JdbcIntersect, LogicalIntersect

public abstract class Intersect
extends SetOp

Relational expression that returns the intersection of the rows of its inputs.

If "all" is true, performs then multiset intersection; otherwise, performs set set intersection (implying no duplicates in the results).

Field Summary

Fields inherited from class org.apache.calcite.rel.core.SetOp

all, inputs, kind

Fields inherited from class org.apache.calcite.rel.AbstractRelNode

digest, id, rowType, traitSet

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Intersect(RelInput input) Creates an Intersect by parsing serialized output.
	Intersect(RelOptCluster cluster, RelTraitSet traits, List<RelNode> inputs, boolean all) Creates an Intersect.

Method Summary

Methods

Modifier and Type	Method and Description
double	getRows() Returns an estimate of the number of rows this relational expression will return.
boolean	isKey(ImmutableBitSet columns) Returns whether the result of this relational expression is uniquely identified by this columns with the given ordinals.

Methods inherited from class org.apache.calcite.rel.core.SetOp

copy, copy, deriveRowType, explainTerms, getInputs, isHomogeneous, replaceInput

Methods inherited from class org.apache.calcite.rel.AbstractRelNode

accept, accept, childrenAccept, collectVariablesSet, collectVariablesUsed, computeDigest, computeSelfCost, explain, getChildExps, getCluster, getCollationList, getConvention, getCorrelVariable, getDescription, getDigest, getExpectedInputRowType, getId, getInput, getQuery, getRelTypeName, getRowType, getTable, getTraitSet, getVariablesStopped, isDistinct, isValid, metadata, onRegister, recomputeDigest, register, sole, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

Intersect

public Intersect(RelOptCluster cluster,
         RelTraitSet traits,
         List<RelNode> inputs,
         boolean all)

Creates an Intersect.

Intersect

protected Intersect(RelInput input)

Creates an Intersect by parsing serialized output.

Method Detail

getRows

public double getRows()

Description copied from interface: RelNode

Returns an estimate of the number of rows this relational expression will return.

NOTE jvs 29-Mar-2006: Don't call this method directly. Instead, use RelMetadataQuery.getRowCount(org.apache.calcite.rel.RelNode), which gives plugins a chance to override the rel's default ideas about row count.

Specified by:

getRows in interface RelNode

Overrides:

getRows in class AbstractRelNode

Returns:

Estimate of the number of rows this relational expression will return

isKey

public boolean isKey(ImmutableBitSet columns)

Description copied from interface: RelNode

Returns whether the result of this relational expression is uniquely identified by this columns with the given ordinals.

For example, if this relational expression is a LogicalTableScan to T(A, B, C, D) whose key is (A, B), then isKey([0, 1]) yields true, and isKey([0]) and isKey([0, 2]) yields false.

Specified by:

isKey in interface RelNode

Overrides:

isKey in class SetOp

Parameters:

columns - Ordinals of key columns

Returns:

Whether the given columns are a key or a superset of a key