duckdb::ColumnDataCollection Class Reference

#include <duckdb.hpp>

Collaboration diagram for duckdb::ColumnDataCollection:

Public Member Functions
DUCKDB_API	ColumnDataCollection (Allocator &allocator, vector< LogicalType > types)
	Constructs an in-memory column data collection from an allocator.
DUCKDB_API	ColumnDataCollection (Allocator &allocator)
	Constructs an empty (but valid) in-memory column data collection from an allocator.
DUCKDB_API	ColumnDataCollection (BufferManager &buffer_manager, vector< LogicalType > types, ColumnDataCollectionLifetime lifetime=ColumnDataCollectionLifetime::REGULAR)
	Constructs a buffer-managed column data collection.
DUCKDB_API	ColumnDataCollection (ClientContext &context, vector< LogicalType > types, ColumnDataAllocatorType type=ColumnDataAllocatorType::BUFFER_MANAGER_ALLOCATOR, ColumnDataCollectionLifetime lifetime=ColumnDataCollectionLifetime::REGULAR)
	Constructs either an in-memory or a buffer-managed column data collection.
DUCKDB_API	ColumnDataCollection (ColumnDataCollection &parent)
DUCKDB_API	ColumnDataCollection (shared_ptr< ColumnDataAllocator > allocator, vector< LogicalType > types)
vector< LogicalType > &	Types ()
	The types of columns in the ColumnDataCollection.
const vector< LogicalType > &	Types () const
const idx_t &	Count () const
	The amount of rows in the ColumnDataCollection.
idx_t	ColumnCount () const
	The amount of columns in the ColumnDataCollection.
idx_t	SizeInBytes () const
	The size (in bytes) of this ColumnDataCollection.
idx_t	AllocationSize () const
	The allocation size (in bytes) of this ColumnDataCollection - this property is cached.
void	SetPartitionIndex (idx_t index)
	Sets the partition index of this ColumnDataCollection.
DUCKDB_API Allocator &	GetAllocator () const
	Get the allocator.
DUCKDB_API void	InitializeAppend (ColumnDataAppendState &state)
	Initializes an Append state - useful for optimizing many appends made to the same column data collection.
DUCKDB_API void	Append (ColumnDataAppendState &state, DataChunk &new_chunk)
	Append a DataChunk to this ColumnDataCollection using the specified append state.
DUCKDB_API void	InitializeScanChunk (DataChunk &chunk) const
	Initializes a chunk with the correct types that can be used to call Scan.
DUCKDB_API void	InitializeScanChunk (Allocator &allocator, DataChunk &chunk) const
DUCKDB_API void	InitializeScanChunk (ColumnDataScanState &state, DataChunk &chunk) const
	Initializes a chunk with the correct types for a given scan state.
DUCKDB_API void	InitializeScan (ColumnDataScanState &state, ColumnDataScanProperties properties=ColumnDataScanProperties::ALLOW_ZERO_COPY) const
	Initializes a Scan state for scanning all columns.
DUCKDB_API void	InitializeScan (ColumnDataScanState &state, vector< column_t > column_ids, ColumnDataScanProperties properties=ColumnDataScanProperties::ALLOW_ZERO_COPY) const
	Initializes a Scan state for scanning a subset of the columns.
DUCKDB_API void	InitializeScan (ColumnDataParallelScanState &state, ColumnDataScanProperties properties=ColumnDataScanProperties::ALLOW_ZERO_COPY) const
	Initialize a parallel scan over the column data collection over all columns.
DUCKDB_API void	InitializeScan (ColumnDataParallelScanState &state, vector< column_t > column_ids, ColumnDataScanProperties properties=ColumnDataScanProperties::ALLOW_ZERO_COPY) const
	Initialize a parallel scan over the column data collection over a subset of the columns.
DUCKDB_API bool	Scan (ColumnDataScanState &state, DataChunk &result) const
	Scans a DataChunk from the ColumnDataCollection.
DUCKDB_API bool	Scan (ColumnDataParallelScanState &state, ColumnDataLocalScanState &lstate, DataChunk &result) const
	Scans a DataChunk from the ColumnDataCollection.
DUCKDB_API void	Append (DataChunk &new_chunk)
	Append a DataChunk directly to this ColumnDataCollection - calls InitializeAppend and Append internally.
DUCKDB_API void	Combine (ColumnDataCollection &other)
	Appends the other ColumnDataCollection to this, destroying the other data collection.
DUCKDB_API void	Verify ()
DUCKDB_API string	ToString () const
DUCKDB_API void	Print () const
DUCKDB_API void	Reset ()
DUCKDB_API idx_t	ChunkCount () const
	Returns the number of data chunks present in the ColumnDataCollection.
DUCKDB_API void	FetchChunk (idx_t chunk_idx, DataChunk &result) const
	Fetch an individual chunk from the ColumnDataCollection.
DUCKDB_API ColumnDataChunkIterationHelper	Chunks () const
DUCKDB_API ColumnDataChunkIterationHelper	Chunks (vector< column_t > column_ids) const
DUCKDB_API ColumnDataRowIterationHelper	Rows () const
DUCKDB_API ColumnDataRowCollection	GetRows () const
bool	NextScanIndex (ColumnDataScanState &state, idx_t &chunk_index, idx_t &segment_index, idx_t &row_index) const
	Obtains the next scan index to scan from.
bool	PrevScanIndex (ColumnDataScanState &state, idx_t &chunk_index, idx_t &segment_index, idx_t &row_index) const
	Obtains the previous scan index to scan from.
void	ScanAtIndex (ColumnDataParallelScanState &state, ColumnDataLocalScanState &lstate, DataChunk &result, idx_t chunk_index, idx_t segment_index, idx_t row_index) const
	Scans at the indices (obtained from NextScanIndex)
bool	Seek (idx_t row_idx, ColumnDataScanState &state, DataChunk &result) const
void	Initialize (vector< LogicalType > types)
	Initialize the column data collection.
vector< shared_ptr< StringHeap > >	GetHeapReferences ()
	Get references to the string heaps in this ColumnDataCollection.
ColumnDataAllocatorType	GetAllocatorType () const
	Get the allocator type of this ColumnDataCollection.
BufferManager &	GetBufferManager () const
	Get the buffer manager of the allocator.
const vector< unique_ptr< ColumnDataCollectionSegment > > &	GetSegments () const
	Get a vector of the segments in this ColumnDataCollection.
void	Serialize (Serializer &serializer) const

Static Public Member Functions
static bool	ResultEquals (const ColumnDataCollection &left, const ColumnDataCollection &right, string &error_message, bool ordered=false)
static unique_ptr< ColumnDataCollection >	Deserialize (Deserializer &deserializer)

Private Member Functions
void	CreateSegment ()
	Creates a new segment within the ColumnDataCollection.

Static Private Member Functions
static ColumnDataCopyFunction	GetCopyFunction (const LogicalType &type)

Private Attributes
buffer_ptr< ColumnDataAllocator >	allocator
	The Column Data Allocator.
vector< LogicalType >	types
	The types of the stored entries.
idx_t	count
	The number of entries stored in the column data collection.
vector< unique_ptr< ColumnDataCollectionSegment > >	segments
	The data segments of the column data collection.
vector< ColumnDataCopyFunction >	copy_functions
	The set of copy functions.
bool	finished_append
	When the column data collection is marked as finished - new tuples can no longer be appended to it.
optional_idx	partition_index
	Partition index (optional, if partitioned)

Detailed Description

The ColumnDataCollection represents a set of (buffer-managed) data stored in columnar format It is efficient to read and scan

Constructor & Destructor Documentation

ColumnDataCollection()

DUCKDB_API duckdb::ColumnDataCollection::ColumnDataCollection

(

ColumnDataCollection &

parent

)

Creates a column data collection that inherits the blocks to write to. This allows blocks to be shared between multiple column data collections and prevents wasting space. Note that after one CDC inherits blocks from another, the other cannot be written to anymore (i.e. we take ownership of the half-written blocks).

Member Function Documentation

Types() [1/2]

vector< LogicalType > & duckdb::ColumnDataCollection::Types ( )

inline

The types of columns in the ColumnDataCollection.

                                 {
        return types;
    }

Types() [2/2]

const vector< LogicalType > & duckdb::ColumnDataCollection::Types ( ) const

inline

                                             {
        return types;
    }

Count()

const idx_t & duckdb::ColumnDataCollection::Count ( ) const

inline

The amount of rows in the ColumnDataCollection.

                               {
        return count;
    }

ColumnCount()

idx_t duckdb::ColumnDataCollection::ColumnCount ( ) const

inline

The amount of columns in the ColumnDataCollection.

                              {
        return types.size();
    }

Chunks() [1/2]

DUCKDB_API ColumnDataChunkIterationHelper duckdb::ColumnDataCollection::Chunks

(

)

const

Constructs a class that can be iterated over to fetch individual chunks Iterating over this is syntactic sugar over just calling Scan

Chunks() [2/2]

DUCKDB_API ColumnDataChunkIterationHelper duckdb::ColumnDataCollection::Chunks

(

vector< column_t >

column_ids

)

const

Constructs a class that can be iterated over to fetch individual chunks Only the column indexes specified in the column_ids list are scanned

Rows()

DUCKDB_API ColumnDataRowIterationHelper duckdb::ColumnDataCollection::Rows

(

)

const

Constructs a class that can be iterated over to fetch individual rows Note that row iteration is slow, and the .Chunks() method should be used instead

GetRows()

DUCKDB_API ColumnDataRowCollection duckdb::ColumnDataCollection::GetRows

(

)

const

Returns a materialized set of all of the rows in the column data collection Note that usage of this is slow - avoid using this unless the amount of rows is small, or if you do not care about performance

ResultEquals()

static bool duckdb::ColumnDataCollection::ResultEquals ( const ColumnDataCollection &  left, const ColumnDataCollection &  right, string &  error_message, bool  ordered = false  )

static

Compare two column data collections to another. If they are equal according to result equality rules, return true. That means null values are equal, and approx equality is used for floating point values. If they are not equal, return false and fill in the error message.

Seek()

bool duckdb::ColumnDataCollection::Seek	(	idx_t	row_idx,
		ColumnDataScanState &	state,
		DataChunk &	result
	)		const

Seeks to the chunk containing the row. Returns false if it is past the end. Note that the returned chunk will likely not be aligned to the given row but the scan state will provide the actual range

---

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

• external/duckdb/duckdb.hpp