duckdb::BaseFileReader Class Reference

Inheritance diagram for duckdb::BaseFileReader:

Collaboration diagram for duckdb::BaseFileReader:

Public Member Functions
	BaseFileReader (OpenFileInfo file_p)
const vector< MultiFileColumnDefinition > &	GetColumns () const
const string &	GetFileName () const
virtual bool	UseCastMap () const
virtual void	AddVirtualColumn (column_t virtual_column_id)
	Adds a virtual column to be projected at the end.
virtual DUCKDB_API shared_ptr< BaseUnionData >	GetUnionData (idx_t file_idx)
virtual DUCKDB_API unique_ptr< BaseStatistics >	GetStatistics (ClientContext &context, const string &name)
	Get statistics for a specific column.
virtual DUCKDB_API void	PrepareReader (ClientContext &context, GlobalTableFunctionState &)
	Prepare reader for scanning.
virtual bool	TryInitializeScan (ClientContext &context, GlobalTableFunctionState &gstate, LocalTableFunctionState &lstate)=0
	Try to initialize a scan over the reader - this is done while the global lock is held.
virtual void	PrepareScan (ClientContext &context, GlobalTableFunctionState &gstate, LocalTableFunctionState &lstate)
	Prepare a scan - called after TryInitializeScan succeeds - this is done without any lock held.
virtual AsyncResult	Scan (ClientContext &context, GlobalTableFunctionState &global_state, LocalTableFunctionState &local_state, DataChunk &chunk)=0
	Scan a chunk from the read state.
virtual DUCKDB_API void	FinishFile (ClientContext &context, GlobalTableFunctionState &gstate)
	Finish scanning a given file.
virtual DUCKDB_API double	GetProgressInFile (ClientContext &context)
	Get progress within a given file.
virtual string	GetReaderType () const =0
template<class TARGET >
TARGET &	Cast ()
template<class TARGET >
const TARGET &	Cast () const
Public Member Functions inherited from duckdb::enable_shared_from_this< BaseFileReader >
shared_ptr< BaseFileReader >	shared_from_this ()
shared_ptr< BaseFileReader const >	shared_from_this () const

Public Attributes
OpenFileInfo	file
	The file we are reading.
optional_idx	file_list_idx
	(Optionally) The file index (generated by the multi file reader)
vector< MultiFileColumnDefinition >	columns
	The set of columns for the current file.
MultiFileLocalColumnIds< MultiFileLocalColumnId >	column_ids
	The column ids to read from the file.
vector< ColumnIndex >	column_indexes
	The column indexes to read from the file.
unique_ptr< TableFilterSet >	filters
	The set of table filters (adjusted to local indexes)
unordered_map< column_t, unique_ptr< Expression > >	expression_map
unordered_map< column_t, LogicalType >	cast_map
	The final types for various expressions - this is ONLY used if UseCastMap() is explicitly enabled.
unique_ptr< DeleteFilter >	deletion_filter
	(Optionally) The deletion filter (generated by the multi file reader)

Additional Inherited Members
Protected Member Functions inherited from duckdb::enable_shared_from_this< BaseFileReader >
	enable_shared_from_this (enable_shared_from_this const &) noexcept
enable_shared_from_this &	operator= (enable_shared_from_this const &) noexcept

Detailed Description

Parent class of single-file readers - this must be inherited from for readers implementing the MultiFileReader interface

Constructor & Destructor Documentation

BaseFileReader()

duckdb::BaseFileReader::BaseFileReader ( OpenFileInfo  file_p )

inlineexplicit

                                                 : file(std::move(file_p)) {
    }

Member Function Documentation

GetColumns()

const vector< MultiFileColumnDefinition > & duckdb::BaseFileReader::GetColumns ( ) const

inline

                                                                {
        return columns;
    }

GetFileName()

const string & duckdb::BaseFileReader::GetFileName ( ) const

inline

                                      {
        return file.path;
    }

UseCastMap()

virtual bool duckdb::BaseFileReader::UseCastMap ( ) const

inlinevirtual

Whether or not to push casts into the cast map

                                    {
        return false;
    }

AddVirtualColumn()

virtual void duckdb::BaseFileReader::AddVirtualColumn ( column_t  virtual_column_id )

inlinevirtual

Adds a virtual column to be projected at the end.

                                                              {
        throw InternalException("Reader %s does not support AddVirtualColumn", GetReaderType());
    }

GetUnionData()

shared_ptr< BaseUnionData > duckdb::BaseFileReader::GetUnionData ( idx_t  file_idx )

virtual

                                                                     {
    throw NotImplementedException("Union by name not supported for reader of type %s", GetReaderType());
}

GetStatistics()

unique_ptr< BaseStatistics > duckdb::BaseFileReader::GetStatistics ( ClientContext &  context, const string &  name  )

virtual

Get statistics for a specific column.

                                                                                                   {
    return nullptr;
}

PrepareReader()

void duckdb::BaseFileReader::PrepareReader ( ClientContext &  context, GlobalTableFunctionState &    )

virtual

Prepare reader for scanning.

                                                                                     {
}

PrepareScan()

void duckdb::BaseFileReader::PrepareScan ( ClientContext &  context, GlobalTableFunctionState &  gstate, LocalTableFunctionState &  lstate  )

virtual

Prepare a scan - called after TryInitializeScan succeeds - this is done without any lock held.

                                                                                                       {
}

FinishFile()

void duckdb::BaseFileReader::FinishFile ( ClientContext &  context, GlobalTableFunctionState &  gstate  )

virtual

Finish scanning a given file.

                                                                                        {
}

GetProgressInFile()

double duckdb::BaseFileReader::GetProgressInFile ( ClientContext &  context )

virtual

Get progress within a given file.

                                                               {
    return 0;
}

Cast() [1/2]

template<class TARGET >

TARGET & duckdb::BaseFileReader::Cast ( )

inline

                   {
        DynamicCastCheck<TARGET>(this);
        return reinterpret_cast<TARGET &>(*this);
    }

Cast() [2/2]

template<class TARGET >

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

inline

                               {
        DynamicCastCheck<TARGET>(this);
        return reinterpret_cast<const TARGET &>(*this);
    }

Member Data Documentation

expression_map

unordered_map<column_t, unique_ptr<Expression> > duckdb::BaseFileReader::expression_map

Expression to execute for a given column (BEFORE executing the filter) NOTE: this is only set when we have filters - it can be ignored for readers that don't have filter pushdown

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

• external/duckdb/duckdb.cpp