net.sf.farrago.namespace.mdr
Class MedMdrJoinRule

java.lang.Object
  extended by org.eigenbase.relopt.RelOptRule
      extended by net.sf.farrago.namespace.mdr.MedMdrJoinRule

 class MedMdrJoinRule
extends RelOptRule

MedMdrJoinRule is a rule for converting a JoinRel into a MedMdrJoinRel when the join condition navigates an association.

Version:
$Id: //open/dev/farrago/src/net/sf/farrago/namespace/mdr/MedMdrJoinRule.java#20 $
Author:
John V. Sichi

Field Summary
 
Fields inherited from class org.eigenbase.relopt.RelOptRule
ANY, description, operands
 
Constructor Summary
MedMdrJoinRule()
           
 
Method Summary
 CallingConvention getOutConvention()
          Returns the calling convention of the result of firing this rule, null if not known.
 void onMatch(RelOptRuleCall call)
          Receives notification about a rule match.
 
Methods inherited from class org.eigenbase.relopt.RelOptRule
convert, equals, equals, getOperand, getOperands, getOutTrait, hashCode, matches, mergeTraitsAndConvert, mergeTraitsAndConvert, toString
 
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
 

Constructor Detail

MedMdrJoinRule

MedMdrJoinRule()
Method Detail

getOutConvention

public CallingConvention getOutConvention()
Description copied from class: RelOptRule
Returns the calling convention of the result of firing this rule, null if not known.

Overrides:
getOutConvention in class RelOptRule

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)