C++ SDK Documentation  12.0.3
Vertica::DefaultSourceIterator Class Reference
Inheritance diagram for Vertica::DefaultSourceIterator:
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Collaboration diagram for Vertica::DefaultSourceIterator:
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Public Member Functions

 DefaultSourceIterator (std::vector< UDSource * > sources)
 
void cancelUDX (ServerInterface &srvInterface)
 
UnsizedUDSourcecreateNextSource (ServerInterface &srvInterface) __override__
 Create the next UDSource to process. More...
 
virtual void destroy (ServerInterface &srvInterface, NodeSpecifyingPlanContext &planCtxt)
 Tear down this SourceIterator. More...
 
size_t getNumberOfSources () __override__
 indicate an upper bound for the number of sources this factory will produce. More...
 
size_t getSizeOfSource (size_t sourceNum) __override__
 
bool isCanceled () const
 
virtual void setup (ServerInterface &srvInterface, NodeSpecifyingPlanContext &planCtxt)
 Set up this SourceIterator. More...
 

Protected Member Functions

virtual void cancel (ServerInterface &srvInterface)
 

Member Function Documentation

virtual void Vertica::UDXObject::cancel ( ServerInterface srvInterface)
inlineprotectedvirtualinherited

Cancel callback to be overridden by the UDX. Called when the query running the UDX has been canceled.

Note
  • This method will be invoked at most once per UDX object. Once a UDX object has been canceled, it will never be un-canceled.
  • This method may be called from a separate thread, concurrently with other methods of this UDX object (but never the constructor or destructor). Implementations must be thread-safe with all methods of this UDX.
  • This method will be invoked for either an explicit user cancel, or in the event of an error during query execution.

Referenced by Vertica::UDXObject::cancelUDX().

void Vertica::UDXObject::cancelUDX ( ServerInterface srvInterface)
inlineinherited

Cancel callback invoked when the query running the UDX has been canceled. See cancel().

UnsizedUDSource* Vertica::DefaultSourceIterator::createNextSource ( ServerInterface srvInterface)
inlinevirtual

Create the next UDSource to process.

Should return NULL if no further sources are available for processing.

Note that the previous Source may still be open and in use on a different thread when this function is called.

Returns
a new Source instance corresponding to a new input stream

Implements Vertica::SourceIterator.

virtual void Vertica::SourceIterator::destroy ( ServerInterface srvInterface,
NodeSpecifyingPlanContext planCtxt 
)
inlinevirtualinherited

Tear down this SourceIterator.

Should perform clean-up that should not take place in the destructor due to the exception-handling semantics of destructors.

size_t Vertica::DefaultSourceIterator::getNumberOfSources ( )
inlinevirtual

indicate an upper bound for the number of sources this factory will produce.

If this method returns N, then createNextSource() will be called at most N times ("at most" because it will stop being called when it returns NULL).

Returns
the maximum number of Sources that this factory will produce

Implements Vertica::SourceIterator.

size_t Vertica::DefaultSourceIterator::getSizeOfSource ( size_t  sourceNum)
inlinevirtual
Returns
the raw-data size of the sourceNum'th source that will be produced by createNextSource(). Should return vint_null if the size is unknown.

This value is used as a hint, and is used by the "load_streams" table to display load progress. If incorrect or not set, "load_streams" may contain incorrect or unhelpful information.

Reimplemented from Vertica::SourceIterator.

bool Vertica::UDXObject::isCanceled ( ) const
inlineinherited
Returns
true iff this UDX has been canceled
virtual void Vertica::SourceIterator::setup ( ServerInterface srvInterface,
NodeSpecifyingPlanContext planCtxt 
)
inlinevirtualinherited

Set up this SourceIterator.

Should perform setup that should not take place in the constructor due to the exception-handling semantics of constructors