Poco::Data

template < class C >

class InternalExtraction

File Information

Library: Data
Package: DataCore
Header: Poco/Data/Extraction.h

Description

Vector Data Type specialization for extraction of values from a query result set. Vector bool specialization for extraction of values from a query result set. List Data Type specialization for extraction of values from a query result set. Deque Data Type specialization for extraction of values from a query result set. Container Data Type specialization extension for extraction of values from a query result set.

This class is intended for PocoData internal use - it is used by StatementImpl to automaticaly create internal Extraction in cases when statement returns data and no external storage was supplied. It is later used by RecordSet to retrieve the fetched data after statement execution. It takes ownership of the Column pointer supplied as constructor argument. Column object, in turn owns the data container pointer.

InternalExtraction objects can not be copied or assigned.

Inheritance

Direct Base Classes: Extraction < C >

All Base Classes: Extraction < C >

Member Summary

Member Functions: column, isNull, reset, value

Types Aliases

Ptr

using Ptr = SharedPtr < Type >;

Type

using Type = Extraction < ValType >;

ValPtr

using ValPtr = SharedPtr < ValType >;

ValType

using ValType = typename C::value_type;

Constructors

InternalExtraction inline

InternalExtraction(
    C & result,
    Column < C > * pColumn,
    const Position & pos = Position (0)
);

Destructor

~InternalExtraction inline

~InternalExtraction();

Destroys InternalExtraction.

Member Functions

column inline

const Column < C > & column() const;

isNull inline

bool isNull(
    std::size_t row
) const;

reset inline

void reset();

value inline

const ValType & value(
    int index
) const;

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