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 
InternalExtraction(
C & result,
Column < C > * pColumn,
const Position & pos = Position (0)
);
Creates InternalExtraction.
Destructor
~InternalExtraction
Destroys InternalExtraction.
Member Functions
column
const Column < C > & column() const;
isNull
bool isNull(
std::size_t row
) const;
reset
void reset();
value
const ValType & value(
int index
) const;