Class UnionRel

  extended by org.eigenbase.rel.AbstractRelNode
      extended by org.eigenbase.rel.SetOpRel
          extended by org.eigenbase.rel.UnionRelBase
              extended by org.eigenbase.rel.UnionRel
All Implemented Interfaces:
Cloneable, RelNode

public final class UnionRel
extends UnionRelBase

UnionRel returns the union of the rows of its inputs, optionally eliminating duplicates.

23 September, 2001
$Id: //open/dev/farrago/src/org/eigenbase/rel/ $

Field Summary
Fields inherited from class org.eigenbase.rel.SetOpRel
all, inputs
Fields inherited from class org.eigenbase.rel.AbstractRelNode
digest, id, nextId, rowType, traits
Fields inherited from interface org.eigenbase.rel.RelNode
Constructor Summary
UnionRel(RelOptCluster cluster, RelNode[] inputs, boolean all)
Method Summary
 UnionRel clone()
          Clones this RelNode.
 UnionRel clone(RelNode[] inputs, boolean all)
Methods inherited from class org.eigenbase.rel.UnionRelBase
estimateRowCount, getRows
Methods inherited from class org.eigenbase.rel.SetOpRel
deriveRowType, explain, getInputs, isDistinct, isHomogeneous, isHomogeneous, replaceInput
Methods inherited from class org.eigenbase.rel.AbstractRelNode
childrenAccept, cloneTraits, collectVariablesSet, collectVariablesUsed, computeDigest, computeSelfCost, getChildExps, getCluster, getCollationList, getConvention, getCorrelVariable, getDescription, getDigest, getExpectedInputRowType, getId, getInput, getOrCreateCorrelVariable, getQuery, getRelTypeName, getRowType, getTable, getTraits, getVariablesStopped, inheritTraitsFrom, isAccessTo, isValid, onRegister, recomputeDigest, register, registerCorrelVariable, setCorrelVariable, toString
Methods inherited from class java.lang.Object
equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail


public UnionRel(RelOptCluster cluster,
                RelNode[] inputs,
                boolean all)
Method Detail


public UnionRel clone()
Description copied from interface: RelNode
Clones this RelNode.

Traits of the RelNode must be explicitly cloned, using AbstractRelNode.inheritTraitsFrom(AbstractRelNode), as the RelNode may have traits of which it has no knowledge. Example implementation:

     public MyRelNode clone()
         MyRelNode clone = new MyRelNode(...);
         return clone;
N.B.: This method must be overridden whenever an existing, concrete RelNode is extended. Otherwise, calling clone() will produce a differently typed RelNode, resulting in invalid or incorrect query plans.

Specified by:
clone in interface RelNode
Specified by:
clone in class AbstractRelNode
a clone of this RelNode


public UnionRel clone(RelNode[] inputs,
                      boolean all)
Specified by:
clone in class SetOpRel