Reference to one row in a result. More...

#include <row.hxx>

Inheritance diagram for pqxx::row:

Public Types
using	size_type = row_size_type

using	difference_type = row_difference_type

using	const_iterator = const_row_iterator

using	iterator = const_iterator

using	reference = field

using	pointer = const_row_iterator

using	const_reverse_iterator = const_reverse_row_iterator

using	reverse_iterator = const_reverse_iterator

Public Member Functions
	row ()=default

	row (row &&)=default

	row (row const &)=default

row &	operator= (row const &)=default

row &	operator= (row &&)=default

const_iterator	begin () const noexcept

const_iterator	cbegin () const noexcept

const_iterator	end () const noexcept

const_iterator	cend () const noexcept

result::size_type	num () const

row	slice (size_type sbegin, size_type send) const

PQXX_PURE bool	empty () const noexcept

template<typename Tuple >
void	to (Tuple &t) const
	Extract entire row's values into a tuple. More...

template<typename... TYPE>
std::tuple< TYPE... >	as () const

Comparison
PQXX_PURE bool	operator== (row const &) const noexcept

bool	operator!= (row const &rhs) const noexcept

Column information
size_type	column_number (zview col_name) const
	Number of given column (throws exception if it doesn't exist). More...

oid	column_type (size_type) const
	Return a column's type. More...

oid	column_type (zview col_name) const
	Return a column's type. More...

oid	column_table (size_type col_num) const
	What table did this column come from? More...

oid	column_table (zview col_name) const
	What table did this column come from? More...

size_type	table_column (size_type) const
	What column number in its table did this result column come from? More...

size_type	table_column (zview col_name) const
	What column number in its table did this result column come from? More...

Protected Member Functions
	row (result const &r, result_size_type i) noexcept

void	check_size (size_type expected) const
	Throw `usage_error` if row size is not `expected`. More...

template<typename Tuple >
void	convert (Tuple &t) const
	Convert entire row to tuple fields, without checking row size. More...

Protected Attributes
result	m_result
	Result set of which this is one row. More...

result::size_type	m_index = 0
	Row number. More...

size_type	m_begin = 0
	First column in slice. This row ignores lower-numbered columns. More...

size_type	m_end = 0
	End column in slice. This row only sees lower-numbered columns. More...

Friends
class	const_row_iterator

class	result

template<typename... T>
class	pqxx::internal::result_iter

class	field

Field access
Swap	iterators

reference	front () const noexcept

reference	back () const noexcept

const_reverse_row_iterator	rbegin () const

const_reverse_row_iterator	crbegin () const

const_reverse_row_iterator	rend () const

const_reverse_row_iterator	crend () const

reference	operator[] (size_type) const noexcept

reference	operator[] (zview col_name) const

reference	at (size_type) const

reference	at (zview col_name) const

size_type	size () const noexcept

Swap not rows void	swap (row &) noexcept

result::size_type	rownumber () const noexcept
	Row number, assuming this is a real row and not end()/rend(). More...

Detailed Description

Reference to one row in a result.

A row represents one row (also called a row) in a query result set. It also acts as a container mapping column numbers or names to field values (see below):

cout << row["date"].c_str() << ": " << row["name"].c_str() << endl;

The row itself acts like a (non-modifyable) container, complete with its own const_iterator and const_reverse_iterator.

Member Typedef Documentation

◆ const_iterator

using pqxx::row::const_iterator = const_row_iterator

◆ const_reverse_iterator

using pqxx::row::const_reverse_iterator = const_reverse_row_iterator

◆ difference_type

using pqxx::row::difference_type = row_difference_type

◆ iterator

using pqxx::row::iterator = const_iterator

◆ pointer

using pqxx::row::pointer = const_row_iterator

◆ reference

using pqxx::row::reference = field

◆ reverse_iterator

using pqxx::row::reverse_iterator = const_reverse_iterator

◆ size_type

using pqxx::row::size_type = row_size_type

Constructor & Destructor Documentation

◆ row() [1/4]

pqxx::row::row ( )

default

◆ row() [2/4]

pqxx::row::row ( row && )

default

◆ row() [3/4]

pqxx::row::row ( row const & )

default

◆ row() [4/4]

pqxx::row::row	(	result const &	r,
		result_size_type	i
	)

protectednoexcept

Implementation of the pqxx::result class and support classes.

pqxx::result represents the set of result rows from a database query.

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.

Member Function Documentation

◆ as()

template<typename... TYPE>

std::tuple<TYPE...> pqxx::row::as ( ) const

◆ at() [1/2]

pqxx::field pqxx::row::at ( size_type i ) const

References operator[](), and size().

Referenced by pqxx::const_reverse_result_iterator::const_reverse_result_iterator(), pqxx::connection::get_variable(), pqxx::const_result_iterator::operator*(), and operator[]().

◆ at() [2/2]

pqxx::field pqxx::row::at ( zview col_name ) const

Address field by name.

Warning: This is much slower than indexing by number, or iterating.

References column_number(), and m_begin.

◆ back()

pqxx::row::reference pqxx::row::back ( ) const

noexcept

References m_end.

Referenced by pqxx::const_reverse_result_iterator::const_reverse_result_iterator(), and pqxx::const_result_iterator::operator*().

◆ begin()

pqxx::row::const_iterator pqxx::row::begin ( ) const

noexcept

References m_begin.

Referenced by cbegin(), and rend().

◆ cbegin()

pqxx::row::const_iterator pqxx::row::cbegin ( ) const

noexcept

References begin().

◆ cend()

pqxx::row::const_iterator pqxx::row::cend ( ) const

noexcept

References end().

◆ check_size()

void pqxx::row::check_size ( size_type expected ) const

protected

Throw usage_error if row size is not expected.

◆ column_number()

pqxx::row::size_type pqxx::row::column_number ( zview col_name ) const

Number of given column (throws exception if it doesn't exist).

References pqxx::result::column_name(), pqxx::result::column_number(), m_begin, m_end, and m_result.

Referenced by at().

◆ column_table() [1/2]

pqxx::oid pqxx::row::column_table ( size_type col_num ) const

What table did this column come from?

References pqxx::result::column_table(), m_begin, and m_result.

◆ column_table() [2/2]

oid pqxx::row::column_table ( zview col_name ) const

What table did this column come from?

◆ column_type() [1/2]

pqxx::oid pqxx::row::column_type ( size_type col_num ) const

Return a column's type.

References pqxx::result::column_type(), m_begin, and m_result.

◆ column_type() [2/2]

oid pqxx::row::column_type ( zview col_name ) const

Return a column's type.

◆ convert()

template<typename Tuple >

void pqxx::row::convert ( Tuple & t ) const

protected

Convert entire row to tuple fields, without checking row size.

◆ crbegin()

pqxx::row::const_reverse_iterator pqxx::row::crbegin ( ) const

References rbegin().

◆ crend()

pqxx::row::const_reverse_iterator pqxx::row::crend ( ) const

References rend().

◆ empty()

bool pqxx::row::empty ( ) const

noexcept

References m_begin, and m_end.

◆ end()

pqxx::row::const_iterator pqxx::row::end ( ) const

noexcept

References m_end.

Referenced by cend(), and rbegin().

◆ front()

pqxx::row::reference pqxx::row::front ( ) const

noexcept

References m_begin.

Referenced by pqxx::const_reverse_result_iterator::const_reverse_result_iterator(), pqxx::transaction_base::exec1(), pqxx::transaction_base::exec_params1(), pqxx::transaction_base::exec_prepared1(), and pqxx::const_result_iterator::operator*().

◆ num()

result::size_type pqxx::row::num ( ) const

Referenced by pqxx::const_result_iterator::operator-().

◆ operator!=()

bool pqxx::row::operator!= ( row const & rhs ) const

noexcept

◆ operator=() [1/2]

row& pqxx::row::operator= ( row const & )

default

Referenced by pqxx::const_result_iterator::operator=().

◆ operator=() [2/2]

row& pqxx::row::operator= ( row && )

default

◆ operator==()

bool pqxx::row::operator== ( row const & rhs ) const

noexcept

References size().

◆ operator[]() [1/2]

pqxx::row::reference pqxx::row::operator[] ( size_type i ) const

noexcept

References m_begin.

Referenced by at().

◆ operator[]() [2/2]

pqxx::row::reference pqxx::row::operator[] ( zview col_name ) const

Address field by name.

Warning: This is much slower than indexing by number, or iterating.

References at().

◆ rbegin()

pqxx::row::const_reverse_iterator pqxx::row::rbegin ( ) const

References end().

Referenced by crbegin().

◆ rend()

pqxx::row::const_reverse_iterator pqxx::row::rend ( ) const

References begin().

Referenced by crend().

◆ rownumber()

result::size_type pqxx::row::rownumber ( ) const

noexcept

Row number, assuming this is a real row and not end()/rend().

Referenced by pqxx::const_reverse_result_iterator::const_reverse_result_iterator(), and pqxx::const_result_iterator::operator*().

◆ size()

size_type pqxx::row::size ( ) const

noexcept

Referenced by at(), operator==(), and slice().

◆ slice()

pqxx::row pqxx::row::slice	(	size_type	sbegin,
		size_type	send
	)		const

Produce a slice of this row, containing the given range of columns.

The slice runs from the range's starting column to the range's end column, exclusive. It looks just like a normal result row, except slices can be empty.

Warning: Slicing is a relatively new feature, and not all software may be prepared to deal with empty slices. If there is any chance that your program might be creating empty slices and passing them to code that may not be designed with the possibility of empty rows in mind, be sure to test for that case.

References m_begin, and size().

◆ swap()

void pqxx::row::swap ( row & rhs )

noexcept

References m_begin, m_end, m_index, m_result, and pqxx::result::swap().

Referenced by pqxx::const_result_iterator::swap().

◆ table_column() [1/2]

pqxx::row::size_type pqxx::row::table_column ( size_type col_num ) const

What column number in its table did this result column come from?

A meaningful answer can be given only if the column in question comes directly from a column in a table. If the column is computed in any other way, a logic_error will be thrown.

Parameters

col_num a zero-based column number in this result set

Returns: a zero-based column number in originating table

References m_begin, m_result, and pqxx::result::table_column().

◆ table_column() [2/2]

size_type pqxx::row::table_column ( zview col_name ) const

What column number in its table did this result column come from?

◆ to()

template<typename Tuple >

void pqxx::row::to ( Tuple & t ) const

Extract entire row's values into a tuple.

Converts to the types of the tuple's respective fields.

Friends And Related Function Documentation

◆ const_row_iterator

friend class const_row_iterator

friend

◆ field

friend class field

friend

◆ pqxx::internal::result_iter

template<typename... T>

friend class pqxx::internal::result_iter

friend

◆ result

friend class result

friend

Member Data Documentation

◆ iterators

Swap pqxx::row::iterators

◆ m_begin

size_type pqxx::row::m_begin = 0

protected

First column in slice. This row ignores lower-numbered columns.

Referenced by at(), begin(), column_number(), column_table(), column_type(), empty(), front(), operator[](), slice(), swap(), and table_column().

◆ m_end

size_type pqxx::row::m_end = 0

protected

End column in slice. This row only sees lower-numbered columns.

Referenced by back(), column_number(), empty(), end(), and swap().

◆ m_index

result::size_type pqxx::row::m_index = 0

protected

Row number.

You'd expect this to be unsigned, but due to the way reverse iterators are related to regular iterators, it must be allowed to underflow to -1.

Referenced by pqxx::const_result_iterator::operator!=(), pqxx::const_result_iterator::operator<(), pqxx::const_result_iterator::operator<=(), pqxx::const_result_iterator::operator==(), pqxx::const_result_iterator::operator>(), pqxx::const_result_iterator::operator>=(), and swap().

◆ m_result

result pqxx::row::m_result

protected

Result set of which this is one row.

Referenced by column_number(), column_table(), column_type(), pqxx::field::field(), swap(), and table_column().

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

row.hxx
row.cxx

Public Types

Public Member Functions

Protected Member Functions

Protected Attributes

Friends

Field access

Detailed Description

Member Typedef Documentation

◆ const_iterator

◆ const_reverse_iterator

◆ difference_type

◆ iterator

◆ pointer

◆ reference

◆ reverse_iterator

◆ size_type

Constructor & Destructor Documentation

◆ row() [1/4]

◆ row() [2/4]

◆ row() [3/4]

◆ row() [4/4]

Member Function Documentation

◆ as()

◆ at() [1/2]

◆ at() [2/2]

◆ back()

◆ begin()

◆ cbegin()

◆ cend()

◆ check_size()

◆ column_number()

◆ column_table() [1/2]

◆ column_table() [2/2]

◆ column_type() [1/2]

◆ column_type() [2/2]

◆ convert()

◆ crbegin()

◆ crend()

◆ empty()

◆ end()

◆ front()

◆ num()

◆ operator!=()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ operator==()

◆ operator[]() [1/2]

◆ operator[]() [2/2]

◆ rbegin()

◆ rend()

◆ rownumber()

◆ size()

◆ slice()

◆ swap()

◆ table_column() [1/2]

◆ table_column() [2/2]

◆ to()

Friends And Related Function Documentation

◆ const_row_iterator

◆ field

◆ pqxx::internal::result_iter

◆ result

Member Data Documentation

◆ iterators

◆ m_begin

◆ m_end

◆ m_index

◆ m_result