#include <userver/storages/postgres/result_set.hpp>

Detailed Description

Data row in a result set This class is a mere accessor to underlying result set data buffer, must not be used outside of result set life scope.

Mimics field container

Definition at line 397 of file result_set.hpp.

Inheritance diagram for storages::postgres::Row:

Public Member Functions
Field container interface
size_type	Size () const
	Number of fields.

Forward iteration
const_iterator	cbegin () const

const_iterator	begin () const

const_iterator	cend () const

const_iterator	end () const

Reverse iteration
const_reverse_iterator	crbegin () const

const_reverse_iterator	rbegin () const

const_reverse_iterator	crend () const

const_reverse_iterator	rend () const

reference	operator[] (size_type index) const
	Field access by index.

reference	operator[] (const std::string &name) const
	Field access field by name.

Field container concept
using	size_type = std::size_t

using	const_iterator = ConstFieldIterator

using	const_reverse_iterator = ReverseConstFieldIterator

using	value_type = Field

using	reference = Field

using	pointer = const_iterator

size_type	RowIndex () const

RowDescription	GetDescription () const

Access to row's data
class	ResultSet

template<typename T >
void	To (T &&val) const

template<typename T >
void	To (T &&val, RowTag) const

template<typename T >
void	To (T &&val, FieldTag) const

template<typename... T>
void	To (T &&... val) const
	Read fields into variables in order of their appearance in the row.

template<typename T , typename... Y>
auto	As () const
	Parse values from the row and return the result.

template<typename T >
T	As (RowTag) const
	Returns T initialized with values of the row.

template<typename T >
T	As (FieldTag) const
	Returns T initialized with a single column value of the row.

template<typename... T>
void	To (const std::initializer_list< std::string > &names, T &&... val) const
	Read fields into variables in order of their names in the first argument.

template<typename... T>
std::tuple< T... >	As (const std::initializer_list< std::string > &names) const

template<typename... T>
void	To (const std::initializer_list< size_type > &indexes, T &&... val) const

template<typename... T>
std::tuple< T... >	As (const std::initializer_list< size_type > &indexes) const

size_type	IndexOfName (const std::string &) const

FieldView	GetFieldView (size_type index) const

	Row (detail::ResultWrapperPtr res, size_type row)

Iteration support
bool	IsValid () const

int	Compare (const Row &rhs) const

std::ptrdiff_t	Distance (const Row &rhs) const

Row &	Advance (std::ptrdiff_t)

Member Typedef Documentation

◆ const_iterator

using storages::postgres::Row::const_iterator = ConstFieldIterator

Definition at line 402 of file result_set.hpp.

◆ const_reverse_iterator

using storages::postgres::Row::const_reverse_iterator = ReverseConstFieldIterator

Definition at line 403 of file result_set.hpp.

◆ pointer

using storages::postgres::Row::pointer = const_iterator

Definition at line 407 of file result_set.hpp.

◆ reference

using storages::postgres::Row::reference = Field

Definition at line 406 of file result_set.hpp.

◆ size_type

using storages::postgres::Row::size_type = std::size_t

Definition at line 401 of file result_set.hpp.

◆ value_type

using storages::postgres::Row::value_type = Field

Definition at line 405 of file result_set.hpp.

Constructor & Destructor Documentation

◆ Row()

storages::postgres::Row::Row	(	detail::ResultWrapperPtr	res,
		size_type	row )

inlineprotected

Definition at line 532 of file result_set.hpp.

Member Function Documentation

◆ As() [1/5]

template<typename T , typename... Y>

auto storages::postgres::Row::As ( ) const

Parse values from the row and return the result.

If there are more than one type arguments to the function, it will return a tuple of those types.

If there is a single type argument to the function, it will read the first and the only column of the row or the whole row to the row type (depending on C++ to PosgreSQL mapping presence) and return plain value of this type.

See also: To(T&&)

Definition at line 880 of file result_set.hpp.

◆ As() [2/5]

template<typename... T>

std::tuple< T... > storages::postgres::Row::As ( const std::initializer_list< size_type > & indexes ) const

Definition at line 924 of file result_set.hpp.

◆ As() [3/5]

template<typename... T>

std::tuple< T... > storages::postgres::Row::As ( const std::initializer_list< std::string > & names ) const

Definition at line 902 of file result_set.hpp.

◆ As() [4/5]

template<typename T >

T storages::postgres::Row::As ( FieldTag ) const

inline

Returns T initialized with a single column value of the row.

  auto result = GetConn()->Execute("select ROW($1, $2)", 42, 3.14);
 
  using TupleType = std::tuple<int, double>;
  auto tuple = result.AsSingleRow<TupleType>(storages::postgres::kFieldTag);
  EXPECT_EQ(std::get<0>(tuple), 42);

Definition at line 505 of file result_set.hpp.

◆ As() [5/5]

template<typename T >

T storages::postgres::Row::As ( RowTag ) const

inline

Returns T initialized with values of the row.

  const auto res = GetConn()->Execute("select $1, $2", 42, "foobar");
 
  using TupleType = std::tuple<int, std::string>;
  auto tuple = res.AsSingleRow<TupleType>(storages::postgres::kRowTag);
  EXPECT_EQ(std::get<0>(tuple), 42);
  EXPECT_EQ(std::get<1>(tuple), "foobar");

Definition at line 496 of file result_set.hpp.

◆ begin()

const_iterator storages::postgres::Row::begin ( ) const

inline

Definition at line 421 of file result_set.hpp.

◆ end()

const_iterator storages::postgres::Row::end ( ) const

inline

Definition at line 423 of file result_set.hpp.

◆ GetDescription()

RowDescription storages::postgres::Row::GetDescription ( ) const

inline

Definition at line 412 of file result_set.hpp.

◆ operator[]() [1/2]

reference storages::postgres::Row::operator[] ( const std::string & name ) const

Field access field by name.

Exceptions

FieldNameDoesntExist if the result set doesn't contain such a field

◆ operator[]() [2/2]

reference storages::postgres::Row::operator[] ( size_type index ) const

Field access by index.

Exceptions

FieldIndexOutOfBounds if index is out of bounds

◆ rbegin()

const_reverse_iterator storages::postgres::Row::rbegin ( ) const

inline

Definition at line 428 of file result_set.hpp.

◆ rend()

const_reverse_iterator storages::postgres::Row::rend ( ) const

inline

Definition at line 430 of file result_set.hpp.

◆ RowIndex()

size_type storages::postgres::Row::RowIndex ( ) const

inline

Definition at line 410 of file result_set.hpp.

◆ To() [1/6]

template<typename... T>

void storages::postgres::Row::To	(	const std::initializer_list< size_type > &	indexes,
		T &&...	val ) const

Read fields into variables in order of their indexes in the first argument

Definition at line 913 of file result_set.hpp.

◆ To() [2/6]

template<typename... T>

void storages::postgres::Row::To	(	const std::initializer_list< std::string > &	names,
		T &&...	val ) const

Read fields into variables in order of their names in the first argument.

Definition at line 891 of file result_set.hpp.

◆ To() [3/6]

template<typename... T>

void storages::postgres::Row::To ( T &&... val ) const

Read fields into variables in order of their appearance in the row.

Definition at line 871 of file result_set.hpp.

◆ To() [4/6]

template<typename T >

void storages::postgres::Row::To ( T && val ) const

Read the contents of the row to a user's row type or read the first column into the value.

If the user tries to read the first column into a variable, it must be the only column in the result set. If the result set contains more than one column, the function will throw NonSingleColumnResultSet. If the result set is OK to contain more than one columns, the first column value should be accessed via row[0].To/As.

If the type is a 'row' type, the function will read the fields of the row into the type's data members.

If the type can be treated as both a row type and a composite type (the type is mapped to a PostgreSQL type), the function will treat the type as a type for the first (and the only) column.

To read the all fields of the row as a row type, the To(T&&, RowTag) should be used.

Definition at line 829 of file result_set.hpp.

◆ To() [5/6]

template<typename T >

void storages::postgres::Row::To	(	T &&	val,
		FieldTag	) const

Function to disambiguate reading the first column to a user's composite type (PostgreSQL composite type in the row initializes user's type). The same as calling To(T&& val) for a T mapped to a PostgreSQL type.

Definition at line 856 of file result_set.hpp.

◆ To() [6/6]

template<typename T >

void storages::postgres::Row::To	(	T &&	val,
		RowTag	) const

Function to disambiguate reading the row to a user's row type (values of the row initialize user's type data members)

Definition at line 834 of file result_set.hpp.

Friends And Related Symbol Documentation

◆ ResultSet

friend class ResultSet

friend

Definition at line 530 of file result_set.hpp.

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

userver/storages/postgres/result_set.hpp

Detailed Description

Public Member Functions

Field container concept

Access to row's data

Iteration support

Member Typedef Documentation

◆ const_iterator

◆ const_reverse_iterator

◆ pointer

◆ reference

◆ size_type

◆ value_type

Constructor & Destructor Documentation

◆ Row()

Member Function Documentation

◆ As() [1/5]

◆ As() [2/5]

◆ As() [3/5]

◆ As() [4/5]

◆ As() [5/5]

◆ begin()

◆ end()

◆ GetDescription()

◆ operator[]() [1/2]

◆ operator[]() [2/2]

◆ rbegin()

◆ rend()

◆ RowIndex()

◆ To() [1/6]

◆ To() [2/6]

◆ To() [3/6]

◆ To() [4/6]

◆ To() [5/6]

◆ To() [6/6]

Friends And Related Symbol Documentation

◆ ResultSet