Interface XPLAINFactoryIF
- All Known Implementing Classes:
XPLAINFactory
public interface XPLAINFactoryIF
This is the factory interface of the XPLAINFactory facility. It extends the
possibilities and provides a convenient protocol to explain queries
on basis of the query execution plan. This plan manfifests in Derby in the
different ResultSets and their associated statistics. The introduction of
this factory interface makes it possible to switch to another implementation
or to easily extend the API.
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Field Summary
Fields -
Method Summary
Modifier and TypeMethodDescriptionvoid
This method gets called when the user switches off the explain facility.This method returns an appropriate visitor to traverse the ResultSetStatistics.
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Field Details
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MODULE
Module name for the monitor's module locating system.- See Also:
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Method Details
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getXPLAINVisitor
This method returns an appropriate visitor to traverse the ResultSetStatistics. Depending on the current configuration, the perfect visitor will be chosen, created and cached by this factory method.- Returns:
- a XPLAINVisitor to traverse the ResultSetStatistics
- Throws:
StandardException
- See Also:
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freeResources
void freeResources()This method gets called when the user switches off the explain facility. The factory destroys for example the cached visitor implementation(s) or releases resources to save memory.
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