com.lucidera.lcs
Class LcsAddDeletionScanRule

java.lang.Object
  org.eigenbase.relopt.RelOptRule
      com.lucidera.lcs.LcsAddDeletionScanRule

public class LcsAddDeletionScanRule
extends RelOptRule

A rule for modifying the input into a row scan to include a scan of the deletion index.

Version:

$Id: //open/dev/farrago/src/com/lucidera/lcs/LcsAddDeletionScanRule.java#10 $

Author:

Zelaine Fong

Field Summary

static LcsAddDeletionScanRule	instanceAnyInput
static LcsAddDeletionScanRule	instanceMinusInput
static LcsAddDeletionScanRule	instanceNoInputs

Fields inherited from class org.eigenbase.relopt.RelOptRule

ANY, description, operands

Constructor Summary

LcsAddDeletionScanRule(RelOptRuleOperand operand, String id)
Creates an LcsAddDeletionScanRule.

Method Summary

private boolean	alreadyCalled(RelOptRuleCall call, boolean alterTable) Determines if the deletion scan is already included in the row scan input, or if this particular instance of the rule shouldn't be fired in favor of another more specific rule instance.
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

instanceNoInputs

public static final LcsAddDeletionScanRule instanceNoInputs

instanceMinusInput

public static final LcsAddDeletionScanRule instanceMinusInput

instanceAnyInput

public static final LcsAddDeletionScanRule instanceAnyInput

Constructor Detail

LcsAddDeletionScanRule

public LcsAddDeletionScanRule(RelOptRuleOperand operand,
                              String id)

Creates an LcsAddDeletionScanRule.

Parameters:

operand - Root operand, must not be null

id - Description of rule

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)

alreadyCalled

private boolean alreadyCalled(RelOptRuleCall call,
                              boolean alterTable)

Determines if the deletion scan is already included in the row scan input, or if this particular instance of the rule shouldn't be fired in favor of another more specific rule instance. The first is done by examining the first input into the row scan and seeing if there's a minus of a search of the deletion index or a search of the deletion index.

Parameters:

call - rule call

alterTable - whether we are preparing ALTER TABLE ADD COLUMN

Returns:

true if this should be fired