OptimizerFactory (Apache Derby V10.14 Internals)

All Known Implementing Classes:

OptimizerFactoryImpl
```
public interface OptimizerFactory
```
This is simply the factory for creating an optimizer.
There is expected to be only one of these configured per database.

Field Summary

Fields
Modifier and Type Field Description

static java.lang.String MODULE
Module name for the monitor's module locating system.

Fields
Modifier and Type	Field	Description
`static java.lang.String`	`MODULE`	Module name for the monitor's module locating system.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`boolean`	`doJoinOrderOptimization()`	Tell whether to do join order optimization.
`CostEstimate`	`getCostEstimate()`	Return a new CostEstimate.
`int`	`getMaxMemoryPerTable()`	Return the maxMemoryPerTable setting, this is used in optimizer, as well as subquery materialization at run time.
`Optimizer`	`getOptimizer(OptimizableList optimizableList, OptimizablePredicateList predicateList, DataDictionary dDictionary, RequiredRowOrdering requiredRowOrdering, int numTablesInQuery, OptimizerPlan overridingPlan, LanguageConnectionContext lcc)`	Only one optimizer level should exist in the database, however, the connection may have multiple instances of that optimizer at a given time.
`boolean`	`supportsOptimizerTrace()`	Return whether or not the optimizer associated with this factory supports optimizer trace.

- Field Detail
  - MODULE
```
static final java.lang.String MODULE
```
    Module name for the monitor's module locating system.
    
    See Also:
    
    Constant Field Values
- Method Detail
  - getOptimizer
```
Optimizer getOptimizer(OptimizableList optimizableList,
                       OptimizablePredicateList predicateList,
                       DataDictionary dDictionary,
                       RequiredRowOrdering requiredRowOrdering,
                       int numTablesInQuery,
                       OptimizerPlan overridingPlan,
                       LanguageConnectionContext lcc)
                throws StandardException
```
    Only one optimizer level should exist in the database, however, the connection may have multiple instances of that optimizer at a given time.
    
    Parameters:
    
    optimizableList - The list of Optimizables to optimize.
    
    predicateList - The list of unassigned OptimizablePredicates.
    
    dDictionary - The DataDictionary to use.
    
    requiredRowOrdering - The required ordering of the rows to come out of the optimized result set
    
    numTablesInQuery - The number of tables in the current query
    
    overridingPlan - (Optional) A complete plan specified by optimizer overrides. Must have been bound already.
    
    lcc - The LanguageConnectionContext RESOLVE - We probably want to pass a subquery list, once we define a new interface for them, so that the Optimizer can out where to attach the subqueries.
    
    Throws:
    
    StandardException - Thrown on error
  - getCostEstimate
```
CostEstimate getCostEstimate()
```
    Return a new CostEstimate.
  - supportsOptimizerTrace
```
boolean supportsOptimizerTrace()
```
    Return whether or not the optimizer associated with this factory supports optimizer trace.
    
    Returns:
    
    Whether or not the optimizer associated with this factory supports optimizer trace.
  - getMaxMemoryPerTable
```
int getMaxMemoryPerTable()
```
    Return the maxMemoryPerTable setting, this is used in optimizer, as well as subquery materialization at run time.
    
    Returns:
    
    maxMemoryPerTable value
  - doJoinOrderOptimization
```
boolean doJoinOrderOptimization()
```
    Tell whether to do join order optimization.
    
    Returns:
    
    true means do join order optimization, false means don't do it.

Interface OptimizerFactory

Field Summary

Method Summary

Field Detail

MODULE

Method Detail

getOptimizer

getCostEstimate

supportsOptimizerTrace

getMaxMemoryPerTable

doJoinOrderOptimization