Class FtrsRemoveRedundantSortRule

  extended by org.eigenbase.relopt.RelOptRule
      extended by net.sf.farrago.namespace.ftrs.FtrsRemoveRedundantSortRule

 class FtrsRemoveRedundantSortRule
extends RelOptRule

FtrsRemoveRedundantSortRule removes instances of SortRel which are already satisfied by the physical ordering produced by an underlying FtrsIndexScanRel.

$Id: //open/dev/farrago/src/net/sf/farrago/namespace/ftrs/ $
John V. Sichi

Field Summary
static FtrsRemoveRedundantSortRule instance
Fields inherited from class org.eigenbase.relopt.RelOptRule
ANY, description, operands
Constructor Summary
private FtrsRemoveRedundantSortRule()
          Creates a FtrsRemoveRedundantSortRule.
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

Field Detail


public static final FtrsRemoveRedundantSortRule instance
Constructor Detail


private FtrsRemoveRedundantSortRule()
Creates a FtrsRemoveRedundantSortRule.

Method Detail


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

getOutConvention in class RelOptRule


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
call - Rule call
See Also: