duckdb::BlockingSample Class Reference

Inheritance diagram for duckdb::BlockingSample:

Collaboration diagram for duckdb::BlockingSample:

Public Member Functions
	BlockingSample (int64_t seed=-1)
virtual void	AddToReservoir (DataChunk &input)=0
	Add a chunk of data to the sample.
virtual unique_ptr< BlockingSample >	Copy () const =0
virtual void	Finalize ()=0
virtual void	Destroy ()
virtual unique_ptr< DataChunk >	GetChunk ()=0
virtual void	Serialize (Serializer &serializer) const
std::pair< double, idx_t >	PopFromWeightQueue ()
	Helper functions needed to merge two reservoirs while respecting weights of sampled rows.
double	GetMinWeightThreshold ()
idx_t	GetPriorityQueueSize ()
template<class TARGET >
TARGET &	Cast ()
template<class TARGET >
const TARGET &	Cast () const

Static Public Member Functions
static unique_ptr< BlockingSample >	Deserialize (Deserializer &deserializer)

Public Attributes
unique_ptr< BaseReservoirSampling >	base_reservoir_sample
SampleType	type
	The sample type.
bool	destroyed
	has the sample been destroyed due to updates to the referenced table

Static Public Attributes
static constexpr const SampleType	TYPE = SampleType::BLOCKING_SAMPLE

Constructor & Destructor Documentation

BlockingSample()

duckdb::BlockingSample::BlockingSample ( int64_t  seed = -1 )

inlineexplicit

        : base_reservoir_sample(make_uniq<BaseReservoirSampling>(seed)), type(SampleType::BLOCKING_SAMPLE),
          destroyed(false) {
    }

~BlockingSample()

virtual duckdb::BlockingSample::~BlockingSample ( )

inlinevirtual

                              {
    }

Member Function Documentation

AddToReservoir()

virtual void duckdb::BlockingSample::AddToReservoir ( DataChunk &  input )

pure virtual

Add a chunk of data to the sample.

Implemented in duckdb::ReservoirSample, and duckdb::ReservoirSamplePercentage.

Copy()

virtual unique_ptr< BlockingSample > duckdb::BlockingSample::Copy ( ) const

pure virtual

Implemented in duckdb::ReservoirSample.

GetChunk()

virtual unique_ptr< DataChunk > duckdb::BlockingSample::GetChunk ( )

pure virtual

Fetches a chunk from the sample. destroy = true should only be used when querying from a sample defined in a query and not a duckdb_table_sample.

Implemented in duckdb::ReservoirSample, and duckdb::ReservoirSamplePercentage.

Cast() [1/2]

template<class TARGET >

TARGET & duckdb::BlockingSample::Cast ( )

inline

                   {
        if (type != TARGET::TYPE && TARGET::TYPE != SampleType::BLOCKING_SAMPLE) {
            throw InternalException("Failed to cast sample to type - sample type mismatch");
        }
        return reinterpret_cast<TARGET &>(*this);
    }

Cast() [2/2]

template<class TARGET >

const TARGET & duckdb::BlockingSample::Cast ( ) const

inline

                               {
        if (type != TARGET::TYPE && TARGET::TYPE != SampleType::BLOCKING_SAMPLE) {
            throw InternalException("Failed to cast sample to type - sample type mismatch");
        }
        return reinterpret_cast<const TARGET &>(*this);
    }

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The documentation for this class was generated from the following file:

• external/duckdb/duckdb.hpp