Interface for User-Defined Transform Function (UDTF). A UDTF operates on a table segment and returns zero or more rows of data. More...

Inheritance diagram for Vertica::TransformFunction:

Collaboration diagram for Vertica::TransformFunction:

Public Member Functions
void	cancelUDX (ServerInterface &srvInterface)

virtual void	destroy (ServerInterface &srvInterface, const SizedColumnTypes &argTypes)

virtual void	destroy (ServerInterface &srvInterface, const SizedColumnTypes &argTypes, SessionParamWriterMap &udSessionParams)

bool	isCanceled () const

virtual void	processPartition (ServerInterface &srvInterface, PartitionReader &input_reader, PartitionWriter &output_writer)=0

virtual void	setup (ServerInterface &srvInterface, const SizedColumnTypes &argTypes)

Protected Member Functions
virtual void	cancel (ServerInterface &srvInterface)

Detailed Description

Interface for User-Defined Transform Function (UDTF). A UDTF operates on a table segment and returns zero or more rows of data.

UDTFs can only be used in the SELECT list of a query. UDTFs are cancelable.

A TransformFunction must have an associated TransformFunctionFactory.

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().

virtual void Vertica::UDXFunction::destroy	(	ServerInterface &	srvInterface,
		const SizedColumnTypes &	argTypes
	)

inlinevirtualinherited

Perform per instance destruction. This function may throw errors

Referenced by Vertica::UDXFunction::destroy().

virtual void Vertica::UDXFunction::destroy	(	ServerInterface &	srvInterface,
		const SizedColumnTypes &	argTypes,
		SessionParamWriterMap &	udSessionParams
	)

inlinevirtualinherited

Perform per instance destruction and write session parameters to be used by UDxs that are invoked after this one returns. This function may throw errors

bool Vertica::UDXObject::isCanceled ( ) const

inlineinherited

Returns: true iff this UDX has been canceled

virtual void Vertica::TransformFunction::processPartition	(	ServerInterface &	srvInterface,
		PartitionReader &	input_reader,
		PartitionWriter &	output_writer
	)

pure virtual

Invoke a user defined transform on a set of rows. As the name suggests, a batch of rows are passed in for every invocation to amortize performance.

Parameters

srvInterface	a ServerInterface object used to communicate with Vertica
input_reader	input rows
output_writer	output location

virtual void Vertica::UDXFunction::setup	(	ServerInterface &	srvInterface,
		const SizedColumnTypes &	argTypes
	)

inlinevirtualinherited

Perform per instance initialization. This function may throw errors.

Public Member Functions

Protected Member Functions

Detailed Description

Member Function Documentation