Class LcsTableProjectionRule

  extended by org.eigenbase.relopt.RelOptRule
      extended by net.sf.farrago.namespace.impl.MedAbstractFennelProjectionRule
          extended by com.lucidera.lcs.LcsTableProjectionRule

public class LcsTableProjectionRule
extends MedAbstractFennelProjectionRule

LcsTableProjectionRule implements the rule for pushing a Projection into a LcsRowScanRel.

$Id: //open/dev/farrago/src/com/lucidera/lcs/ $
Zelaine Fong

Field Summary
static LcsTableProjectionRule instance
Fields inherited from class org.eigenbase.relopt.RelOptRule
ANY, description, operands
Constructor Summary
private LcsTableProjectionRule()
          Creates a LcsTableProjectionRule.
Method Summary
protected  Integer mapProjCol(RexNode exp, List<String> origFieldName, RelDataType rowType)
          Maps a projection expression to its underlying field reference.
 void onMatch(RelOptRuleCall call)
          Receives notification about a rule match.
Methods inherited from class net.sf.farrago.namespace.impl.MedAbstractFennelProjectionRule
createNewRelNode, createProjectionList, getOutConvention, mapFieldRef
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 LcsTableProjectionRule instance
Constructor Detail


private LcsTableProjectionRule()
Creates a LcsTableProjectionRule.

Method Detail


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 MedAbstractFennelProjectionRule
call - Rule call
See Also:


protected Integer mapProjCol(RexNode exp,
                             List<String> origFieldName,
                             RelDataType rowType)
Maps a projection expression to its underlying field reference. Also handles special columns, mapping them to their special column ids.

mapProjCol in class MedAbstractFennelProjectionRule
exp - expression to be mapped
origFieldName - returns field name corresponding to the field reference
rowType - row from which the field reference originated
ordinal representing the projection element