# pqxx::tablewriter Class Reference

Efficiently write data directly to a database table. More...

`#include <tablewriter.hxx>`

Inheritance diagram for pqxx::tablewriter:

[legend]

List of all members.

## Public Types
typedef unsigned | size_type
## Public Member Functions
| tablewriter (transaction_base &, const std::string &WName, const std::string &Null=std::string())
template<typename ITER >
| tablewriter (transaction_base &, const std::string &WName, ITER begincolumns, ITER endcolumns)
| Write only the given sequence of columns.
template<typename ITER >
| tablewriter (transaction_base &, const std::string &WName, ITER begincolumns, ITER endcolumns, const std::string &Null)
| Write only the given sequence of columns, with customized "null" string.
| ~tablewriter () throw ()
template<typename IT >
void | insert (IT Begin, IT End)
template<typename TUPLE >
void | insert (const TUPLE &)
template<typename IT >
void | push_back (IT Begin, IT End)
template<typename TUPLE >
void | push_back (const TUPLE &)
void | reserve (size_type)
template<typename TUPLE >
tablewriter & | operator<< (const TUPLE &)
tablewriter & | operator<< (tablereader &)
| Copy table from one database to another.
template<typename IT >
std::string | generate (IT Begin, IT End) const
| Translate tuple of data to a string in DBMS-specific format.
template<typename TUPLE >
std::string | generate (const TUPLE &) const
virtual void | complete ()
| Finish stream action, check for errors, and detach from transaction.
void | write_raw_line (const std::string &)
| Write line of raw data (e.g. obtained from tablereader.get_raw_line).

## Detailed Description

Efficiently write data directly to a database table.

A tablewriter provides a Spartan but efficient way of writing data tuples into a table. It provides a plethora of STL-like insertion methods: it has insert() methods, push_back(), as well as an overloaded insertion operator (`<<`), and it supports inserters created by std::back_inserter(). All of these are templatized so you can use any container type or iterator range to feed tuples into the table.

Note that in each case, a container or range represents the fields of a single tuple--not a collection of tuples.

## Member Typedef Documentation

typedef unsigned pqxx::tablewriter::size_type

## Constructor & Destructor Documentation

pqxx::tablewriter::tablewriter | ( | transaction_base & | T,
|  | const std::string & | WName,
|  | const std::string & | Null = `std ::string()` |
| ) |  |  |

template<typename ITER >

pqxx::tablewriter::tablewriter | ( | transaction_base & | T,
|  | const std::string & | WName,
|  | ITER | begincolumns,
|  | ITER | endcolumns |
| ) |  |  |

Write only the given sequence of columns.

Since:
  PostgreSQL backend 7.3.

This constructor takes a sequence of names of columns to write to. Only those columns will be written, and they will be taken from your input data in that order.

References pqxx::tablestream::columnlist().

template<typename ITER >

pqxx::tablewriter::tablewriter | ( | transaction_base & | T,
|  | const std::string & | WName,
|  | ITER | begincolumns,
|  | ITER | endcolumns,
|  | const std::string & | Null |
| ) |  |  |

Write only the given sequence of columns, with customized "null" string.

Since:
  PostgreSQL backend 7.3.

This constructor takes a sequence of names of columns to write to. Only those columns will be written, and they will be taken from your input data in that order.

Parameters:

  | Null | the string that is used in your input data to denote null

References pqxx::tablestream::columnlist().

pqxx::tablewriter::~tablewriter | ( |  | ) | throw ()

References pqxx::transaction_base::conn(), pqxx::internal::transactionfocus::m_Trans, and pqxx::internal::transactionfocus::reg_pending_error().

## Member Function Documentation

void pqxx::tablewriter::complete | ( |  | ) | `[virtual]`

Finish stream action, check for errors, and detach from transaction.

It is recommended that you call this function before the tablestream's destructor is run. This function will check any final errors which may not become apparent until the transaction is committed otherwise.

As an added benefit, this will free up the transaction while the tablestream object itself still exists.

Implements pqxx::tablestream.

template<typename TUPLE >

std::string pqxx::tablewriter::generate | ( | const TUPLE & | T | ) | const

References generate().

template<typename IT >

std::string pqxx::tablewriter::generate | ( | IT | Begin,
|  | IT | End |
| ) |  |  | const

Translate tuple of data to a string in DBMS-specific format.

Warning:
  This is definitely not portable between databases.

References pqxx::tablestream::NullStr(), and pqxx::separated_list().

Referenced by generate(), and insert().

template<typename TUPLE >

void pqxx::tablewriter::insert | ( | const TUPLE & | T | ) |

References insert().

template<typename IT >

void pqxx::tablewriter::insert | ( | IT | Begin,
|  | IT | End |
| ) |  |  |

References generate(), and write_raw_line().

Referenced by insert(), operator<<(), and push_back().

pqxx::tablewriter & pqxx::tablewriter::operator<< | ( | pqxx::tablereader & | R | ) |

Copy table from one database to another.

References pqxx::tablereader::get_raw_line(), and write_raw_line().

template<typename TUPLE >

tablewriter & pqxx::tablewriter::operator<< | ( | const TUPLE & | T | ) |

References insert().

template<typename TUPLE >

void pqxx::tablewriter::push_back | ( | const TUPLE & | T | ) |

References insert().

template<typename IT >

void pqxx::tablewriter::push_back | ( | IT | Begin,
|  | IT | End |
| ) |  |  |

References insert().

void pqxx::tablewriter::reserve | ( | size_type |  | ) |

void pqxx::tablewriter::write_raw_line | ( | const std::string & | Line | ) |

Write line of raw data (e.g. obtained from tablereader.get_raw_line).

References pqxx::internal::transactionfocus::m_Trans, and pqxx::transaction_base::WriteCopyLine().

Referenced by insert(), and operator<<().

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

- tablewriter.hxx
- tablewriter.cxx