net.sf.farrago.namespace.mdr
Class MedMdrClassExtent

java.lang.Object
  org.eigenbase.relopt.RelOptAbstractTable
      net.sf.farrago.namespace.impl.MedAbstractColumnSet
          net.sf.farrago.namespace.mdr.MedMdrClassExtent

All Implemented Interfaces:

FarragoMedColumnSet, FarragoQueryColumnSet, RelOptTable, SqlValidatorTable

 class MedMdrClassExtent
extends MedAbstractColumnSet

MedMdrClassExtent represents the relational mapping of a class's extent (stored by MDR) into a queryable set of rows.

Version:

$Id: //open/dev/farrago/src/net/sf/farrago/namespace/mdr/MedMdrClassExtent.java#13 $

Author:

John V. Sichi

Field Summary

(package private) MedMdrNameDirectory	directory
(package private) RefClass	refClass

Fields inherited from class org.eigenbase.relopt.RelOptAbstractTable

name, rowType, schema

Constructor Summary

MedMdrClassExtent(MedMdrNameDirectory directory, FarragoTypeFactory typeFactory, RefClass refClass, String[] foreignName, String[] localName, RelDataType rowType)

Method Summary

double	getRowCount() Returns an estimate of the number of rows in the table.
RelNode	toRel(RelOptCluster cluster, RelOptConnection connection) Converts this table into a relational expression.

Methods inherited from class net.sf.farrago.namespace.impl.MedAbstractColumnSet

getAllowedAccess, getColumnPropertyMap, getCwmColumnSet, getForeignName, getLocalName, getMonotonicity, getPreparingStmt, getQualifiedName, getTableProperties, setAllowedAccess, setCwmColumnSet, setPreparingStmt, toLenientRel, toUdxRel

Methods inherited from class org.eigenbase.relopt.RelOptAbstractTable

getCollationList, getName, getRelOptSchema, getRowType, setRowType

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.eigenbase.relopt.RelOptTable

getCollationList, getRelOptSchema, getRowType

Methods inherited from interface org.eigenbase.sql.validate.SqlValidatorTable

getRowType

Field Detail

directory

final MedMdrNameDirectory directory

refClass

final RefClass refClass

Constructor Detail

MedMdrClassExtent

MedMdrClassExtent(MedMdrNameDirectory directory,
                  FarragoTypeFactory typeFactory,
                  RefClass refClass,
                  String[] foreignName,
                  String[] localName,
                  RelDataType rowType)

Method Detail

getRowCount

public double getRowCount()

Description copied from interface: RelOptTable

Returns an estimate of the number of rows in the table.

Specified by:

getRowCount in interface RelOptTable

Overrides:

getRowCount in class RelOptAbstractTable

toRel

public RelNode toRel(RelOptCluster cluster,
                     RelOptConnection connection)

Description copied from interface: RelOptTable

Converts this table into a relational expression.

The planner calls this method to convert a table into an initial relational expression, generally something abstract, such as a TableAccessRel, then optimizes this expression by applying rules to transform it into more efficient access methods for this table.

Parameters:

cluster - the cluster the relational expression will belong to

connection - the parse tree of the expression which evaluates to a connection object