felix.optimizer
Class CostModel

java.lang.Object
  felix.optimizer.CostModel

public class CostModel
extends java.lang.Object

An object of the cost model used by the optimizer. This class works as a bridge from PostgreSQL's optimizer to Felix's optimizer.

Author:

Ce Zhang

Nested Class Summary

class

CostModel.resultTuple Class for a set of different costs.

Field Summary

double	memoryTradeOff
double	postgreUnit The ratio of postgreSQL's unit cost to page IO cost.

Constructor Summary

CostModel(Felix _felix)
The constructor of CostModel.

Method Summary

void	close() Close the database connection used by CostModel.
double	getCost(java.lang.String sql) Return the cost of the given sql query.
double	getFullMatCost(tuffy.ra.ConjunctiveQuery q, double numberOfBB, double numberOfBF, double numberOfFF, java.util.HashSet<java.lang.String> whichToBound) Return the cost of Fully-Materialization plan for q.
double	getFullViewCost(tuffy.ra.ConjunctiveQuery q, double numberOfBB, double numberOfBF, double numberOfFF, java.util.HashSet<java.lang.String> whichToBound) Return the cost of Fully-View plan for q.
CostModel.resultTuple	getJoinCostBetweenTwoMaterializedTable(tuffy.mln.Literal head, tuffy.ra.ConjunctiveQuery q1, tuffy.ra.ConjunctiveQuery q2, double numberOfBB, double numberOfBF, double numberOfFF, java.util.HashSet<java.lang.String> whichToBound) Return the cost of Hybrid-Materialization plan for query {head :- q1.head, q2.head}.
CostModel.resultTuple	getNewEmptyResultTuple() Return a new CostModel.resultTuple.
void	getPostgreUnit() Estimate postgreUnit.
double	getRows(java.lang.String sql) Return the number of rows returned by the given sql query.
double	getTableSize(java.lang.String tableName) Return the number of rows of the given table.
double	getTableWidth(java.lang.String tableName) Return the width (in bits) of the given table.
double	getWidth(java.lang.String sql) Return the width (in bits) returned by the given sql query.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

postgreUnit

public double postgreUnit

The ratio of postgreSQL's unit cost to page IO cost. This is estimated by some sample queries.

memoryTradeOff

public double memoryTradeOff

Constructor Detail

CostModel

public CostModel(Felix _felix)

The constructor of CostModel. This function will load the evidence file if it is not loaded before.

Parameters:

_felix -

Method Detail

getTableSize

public double getTableSize(java.lang.String tableName)

Return the number of rows of the given table.

Parameters:

tableName -

Returns:

getTableWidth

public double getTableWidth(java.lang.String tableName)

Return the width (in bits) of the given table.

Parameters:

tableName -

Returns:

getNewEmptyResultTuple

public CostModel.resultTuple getNewEmptyResultTuple()

Return a new CostModel.resultTuple.

Returns:

getCost

public double getCost(java.lang.String sql)

Return the cost of the given sql query.

Parameters:

sql -

Returns:

getRows

public double getRows(java.lang.String sql)

Return the number of rows returned by the given sql query.

Parameters:

sql -

Returns:

getWidth

public double getWidth(java.lang.String sql)

Return the width (in bits) returned by the given sql query.

Parameters:

sql -

Returns:

getPostgreUnit

public void getPostgreUnit()

Estimate postgreUnit.

close

public void close()

Close the database connection used by CostModel.

getFullMatCost

public double getFullMatCost(tuffy.ra.ConjunctiveQuery q,
                             double numberOfBB,
                             double numberOfBF,
                             double numberOfFF,
                             java.util.HashSet<java.lang.String> whichToBound)

Return the cost of Fully-Materialization plan for q.

Parameters:

q -

numberOfBB -

numberOfBF -

numberOfFF -

whichToBound -

Returns:

getFullViewCost

public double getFullViewCost(tuffy.ra.ConjunctiveQuery q,
                              double numberOfBB,
                              double numberOfBF,
                              double numberOfFF,
                              java.util.HashSet<java.lang.String> whichToBound)

Return the cost of Fully-View plan for q.

Parameters:

q -

numberOfBB -

numberOfBF -

numberOfFF -

whichToBound -

Returns:

getJoinCostBetweenTwoMaterializedTable

public CostModel.resultTuple getJoinCostBetweenTwoMaterializedTable(tuffy.mln.Literal head,
                                                                    tuffy.ra.ConjunctiveQuery q1,
                                                                    tuffy.ra.ConjunctiveQuery q2,
                                                                    double numberOfBB,
                                                                    double numberOfBF,
                                                                    double numberOfFF,
                                                                    java.util.HashSet<java.lang.String> whichToBound)

Return the cost of Hybrid-Materialization plan for query {head :- q1.head, q2.head}.

Parameters:

q -

numberOfBB -

numberOfBF -

numberOfFF -

whichToBound -

Returns: