org.apache.derby.impl.sql.compile
Class Level2OptimizerFactoryImpl

java.lang.Object
  extended by org.apache.derby.impl.sql.compile.OptimizerFactoryImpl
      extended by org.apache.derby.impl.sql.compile.Level2OptimizerFactoryImpl
All Implemented Interfaces:
ModuleControl, OptimizerFactory

public class Level2OptimizerFactoryImpl
extends OptimizerFactoryImpl

This is simply the factory for creating an optimizer.


Field Summary
 
Fields inherited from class org.apache.derby.impl.sql.compile.OptimizerFactoryImpl
joinStrategySet, maxMemoryPerTable, noTimeout, optimizerId, ruleBasedOptimization, useStatistics
 
Fields inherited from interface org.apache.derby.iapi.sql.compile.OptimizerFactory
MODULE
 
Constructor Summary
Level2OptimizerFactoryImpl()
           
 
Method Summary
 void boot(boolean create, java.util.Properties startParams)
          Boot this module with the given properties.
 CostEstimate getCostEstimate()
          Return a new CostEstimate.
protected  Optimizer getOptimizerImpl(OptimizableList optimizableList, OptimizablePredicateList predList, DataDictionary dDictionary, RequiredRowOrdering requiredRowOrdering, int numTablesInQuery, LanguageConnectionContext lcc)
           
 boolean supportsOptimizerTrace()
          Return whether or not the optimizer associated with this factory supports optimizer trace.
 
Methods inherited from class org.apache.derby.impl.sql.compile.OptimizerFactoryImpl
getMaxMemoryPerTable, getOptimizer, stop
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

Level2OptimizerFactoryImpl

public Level2OptimizerFactoryImpl()
Method Detail

boot

public void boot(boolean create,
                 java.util.Properties startParams)
          throws StandardException
Description copied from interface: ModuleControl
Boot this module with the given properties. Creates a module instance that can be found using the findModule() methods of Monitor. The module can only be found using one of these findModule() methods once this method has returned.

An implementation's boot method can throw StandardException. If it is thrown the module is not registered by the monitor and therefore cannot be found through a findModule(). In this case the module's stop() method is not called, thus throwing this exception must free up any resources.

When create is true the contents of the properties object will be written to the service.properties of the persistent service. Thus any code that requires an entry in service.properties must explicitly place the value in this properties set using the put method.
Typically the properties object contains one or more default properties sets, which are not written out to service.properties. These default sets are how callers modify the create process. In a JDBC connection database create the first set of defaults is a properties object that contains the attributes that were set on the jdbc:derby: URL. This attributes properties set has the second default properties set as its default. This set (which could be null) contains the properties that the user set on their DriverManager.getConnection() call, and are thus not owned by Derby code, and thus must not be modified by Derby code.

When create is false the properties object contains all the properties set in the service.properties file plus a limited number of attributes from the JDBC URL attributes or connection properties set. This avoids properties set by the user compromising the boot process. An example of a property passed in from the JDBC world is the bootPassword for encrypted databases.

Code should not hold onto the passed in properties reference after boot time as its contents may change underneath it. At least after the complete boot is completed, the links to all the default sets will be removed.

Specified by:
boot in interface ModuleControl
Overrides:
boot in class OptimizerFactoryImpl
Throws:
StandardException - Module cannot be started.
See Also:
Monitor, ModuleFactory

supportsOptimizerTrace

public boolean supportsOptimizerTrace()
Description copied from interface: OptimizerFactory
Return whether or not the optimizer associated with this factory supports optimizer trace.

Specified by:
supportsOptimizerTrace in interface OptimizerFactory
Overrides:
supportsOptimizerTrace in class OptimizerFactoryImpl
Returns:
Whether or not the optimizer associated with this factory supports optimizer trace.
See Also:
OptimizerFactory.supportsOptimizerTrace()

getOptimizerImpl

protected Optimizer getOptimizerImpl(OptimizableList optimizableList,
                                     OptimizablePredicateList predList,
                                     DataDictionary dDictionary,
                                     RequiredRowOrdering requiredRowOrdering,
                                     int numTablesInQuery,
                                     LanguageConnectionContext lcc)
                              throws StandardException
Overrides:
getOptimizerImpl in class OptimizerFactoryImpl
Throws:
StandardException

getCostEstimate

public CostEstimate getCostEstimate()
                             throws StandardException
Description copied from interface: OptimizerFactory
Return a new CostEstimate.

Specified by:
getCostEstimate in interface OptimizerFactory
Overrides:
getCostEstimate in class OptimizerFactoryImpl
Throws:
StandardException - Thrown on error
See Also:
OptimizerFactory.getCostEstimate()

Built on Thu 2012-03-29 21:53:33+0000, from revision ???

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