File: //usr/include/pqxx/tablereader.hxx
/*-------------------------------------------------------------------------
*
* FILE
* pqxx/tablereader.hxx
*
* DESCRIPTION
* definition of the pqxx::tablereader class.
* pqxx::tablereader enables optimized batch reads from a database table
* DO NOT INCLUDE THIS FILE DIRECTLY; include pqxx/tablereader instead.
*
* Copyright (c) 2001-2015, Jeroen T. Vermeulen <jtv@xs4all.nl>
*
* See COPYING for copyright license. If you did not receive a file called
* COPYING with this source code, please notify the distributor of this mistake,
* or contact the author.
*
*-------------------------------------------------------------------------
*/
#ifndef PQXX_H_TABLEREADER
#define PQXX_H_TABLEREADER
#include "pqxx/compiler-public.hxx"
#include "pqxx/compiler-internal-pre.hxx"
#include "pqxx/result"
#include "pqxx/tablestream"
namespace pqxx
{
/// @deprecated Efficiently pull data directly out of a table.
/** @warning This class does not work reliably with multibyte encodings. Using
* it with some multi-byte encodings may pose a security risk.
*/
class PQXX_LIBEXPORT tablereader : public tablestream
{
public:
tablereader(transaction_base &,
const std::string &Name,
const std::string &Null=std::string());
template<typename ITER>
tablereader(transaction_base &,
const std::string &Name,
ITER begincolumns,
ITER endcolumns);
template<typename ITER> tablereader(transaction_base &,
const std::string &Name,
ITER begincolumns,
ITER endcolumns,
const std::string &Null);
~tablereader() PQXX_NOEXCEPT;
template<typename TUPLE> tablereader &operator>>(TUPLE &);
operator bool() const PQXX_NOEXCEPT { return !m_Done; }
bool operator!() const PQXX_NOEXCEPT { return m_Done; }
bool get_raw_line(std::string &Line);
template<typename TUPLE>
void tokenize(std::string, TUPLE &) const;
virtual void complete() PQXX_OVERRIDE;
private:
void setup(transaction_base &T,
const std::string &RName,
const std::string &Columns=std::string());
PQXX_PRIVATE void reader_close();
std::string extract_field(
const std::string &,
std::string::size_type &) const;
bool m_Done;
};
template<typename ITER> inline
tablereader::tablereader(transaction_base &T,
const std::string &Name,
ITER begincolumns,
ITER endcolumns) :
namedclass(Name, "tablereader"),
tablestream(T, std::string()),
m_Done(true)
{
setup(T, Name, columnlist(begincolumns, endcolumns));
}
template<typename ITER> inline
tablereader::tablereader(transaction_base &T,
const std::string &Name,
ITER begincolumns,
ITER endcolumns,
const std::string &Null) :
namedclass(Name, "tablereader"),
tablestream(T, Null),
m_Done(true)
{
setup(T, Name, columnlist(begincolumns, endcolumns));
}
template<typename TUPLE>
inline void tablereader::tokenize(std::string Line, TUPLE &T) const
{
std::back_insert_iterator<TUPLE> ins = std::back_inserter(T);
std::string::size_type here=0;
while (here < Line.size()) *ins++ = extract_field(Line, here);
}
template<typename TUPLE>
inline tablereader &pqxx::tablereader::operator>>(TUPLE &T)
{
std::string Line;
if (get_raw_line(Line)) tokenize(Line, T);
return *this;
}
} // namespace pqxx
#include "pqxx/compiler-internal-post.hxx"
#endif