org.apache.calcite.rel.core

Class Uncollect

java.lang.Object

org.apache.calcite.rel.AbstractRelNode

org.apache.calcite.rel.SingleRel

org.apache.calcite.rel.core.Uncollect

All Implemented Interfaces:

Cloneable, RelOptNode, RelNode

Direct Known Subclasses:

EnumerableUncollect

public class Uncollect
extends SingleRel

Relational expression that unnests its input's sole column into a relation.

Like its inverse operation Collect, Uncollect is generally invoked in a nested loop, driven by LogicalCorrelate or similar.

Field Summary

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

digest, id, rowType, traitSet

Constructor Summary

Constructors

Constructor and Description
Uncollect(RelInput input) Creates an Uncollect by parsing serialized output.
Uncollect(RelOptCluster cluster, RelTraitSet traitSet, RelNode child) Creates an Uncollect.

Method Summary

Methods

Modifier and Type	Method and Description
RelNode	copy(RelTraitSet traitSet, List<RelNode> inputs) Creates a copy of this relational expression, perhaps changing traits and inputs.
RelNode	copy(RelTraitSet traitSet, RelNode input)
protected RelDataType	deriveRowType()
static RelDataType	deriveUncollectRowType(RelNode rel) Returns the row type returned by applying the 'UNNEST' operation to a relational expression.

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

childrenAccept, explainTerms, getInput, getInputs, getRows, replaceInput

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

accept, accept, collectVariablesSet, collectVariablesUsed, computeDigest, computeSelfCost, explain, getChildExps, getCluster, getCollationList, getConvention, getCorrelVariable, getDescription, getDigest, getExpectedInputRowType, getId, getInput, getQuery, getRelTypeName, getRowType, getTable, getTraitSet, getVariablesStopped, isDistinct, isKey, 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

Uncollect

public Uncollect(RelOptCluster cluster,
         RelTraitSet traitSet,
         RelNode child)

Creates an Uncollect.

The row type of the child relational expression must contain precisely one column, that column must be a multiset of records.

Parameters:

cluster - Cluster the relational expression belongs to

traitSet - Traits

child - Child relational expression

Uncollect

public Uncollect(RelInput input)

Creates an Uncollect by parsing serialized output.

Method Detail

copy

public final RelNode copy(RelTraitSet traitSet,
           List<RelNode> inputs)

Description copied from interface: RelNode

Creates a copy of this relational expression, perhaps changing traits and inputs.

Sub-classes with other important attributes are encouraged to create variants of this method with more parameters.

Specified by:

copy in interface RelNode

Overrides:

copy in class AbstractRelNode

Parameters:

traitSet - Trait set

inputs - Inputs

Returns:

Copy of this relational expression, substituting traits and inputs

copy

public RelNode copy(RelTraitSet traitSet,
           RelNode input)

deriveRowType

protected RelDataType deriveRowType()

Overrides:

deriveRowType in class SingleRel

deriveUncollectRowType

public static RelDataType deriveUncollectRowType(RelNode rel)

Returns the row type returned by applying the 'UNNEST' operation to a relational expression. The relational expression must have precisely one column, whose type must be a multiset of structs. The return type is the type of that column.