org.eigenbase.rel.rules
Class PullUpAggregateAboveUnionRule

java.lang.Object
  extended by org.eigenbase.relopt.RelOptRule
      extended by org.eigenbase.rel.rules.PullUpAggregateAboveUnionRule

public class PullUpAggregateAboveUnionRule
extends RelOptRule

PullUpAggregateAboveUnionRule implements the rule for pulling AggregateRels beneath a UnionRel so two AggregateRels that are used to remove duplicates can be combined into a single AggregateRel.

This rule only handles cases where the UnionRels still have only two inputs.

Version:
$Id: //open/dev/farrago/src/org/eigenbase/rel/rules/PullUpAggregateAboveUnionRule.java#7 $
Author:
Zelaine Fong

Field Summary
static PullUpAggregateAboveUnionRule instance
           
 
Fields inherited from class org.eigenbase.relopt.RelOptRule
ANY, description, operands
 
Constructor Summary
private PullUpAggregateAboveUnionRule()
          Creates a PullUpAggregateAboveUnionRule.
 
Method Summary
 void onMatch(RelOptRuleCall call)
          Receives notification about a rule match.
 
Methods inherited from class org.eigenbase.relopt.RelOptRule
convert, equals, equals, getOperand, getOperands, getOutConvention, getOutTrait, hashCode, matches, mergeTraitsAndConvert, mergeTraitsAndConvert, toString
 
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
 

Field Detail

instance

public static final PullUpAggregateAboveUnionRule instance
Constructor Detail

PullUpAggregateAboveUnionRule

private PullUpAggregateAboveUnionRule()
Creates a PullUpAggregateAboveUnionRule.

Method Detail

onMatch

public void onMatch(RelOptRuleCall call)
Description copied from class: RelOptRule
Receives notification about a rule match. At the time that this method is called, call.rels holds the set of relational expressions which match the operands to the rule; call.rels[0] is the root expression.

Typically a rule would check that the nodes are valid matches, creates a new expression, then calls back RelOptRuleCall.transformTo(org.eigenbase.rel.RelNode) to register the expression.

Specified by:
onMatch in class RelOptRule
Parameters:
call - Rule call
See Also:
RelOptRule.matches(RelOptRuleCall)