pqxx::largeobject Class Reference

Identity of a large object. More...

#include <largeobject.hxx>

Inheritance diagram for pqxx::largeobject:

Collaboration diagram for pqxx::largeobject:

Public Types
typedef long	size_type

Public Member Functions
	largeobject () throw ()
	Refer to a nonexistent large object (similar to what a null pointer does) More...
	largeobject (dbtransaction &T)
	Create new large object. More...
	largeobject (oid O) throw ()
	Wrap object with given oid. More...
	largeobject (dbtransaction &T, const PGSTD::string &File)
	Import large object from a local file. More...
	largeobject (const largeobjectaccess &O) throw ()
	Take identity of an opened large object. More...
oid	id () const throw ()
	Object identifier. More...
void	remove (dbtransaction &T) const
	Delete large object from database. More...
void	to_file (dbtransaction &T, const PGSTD::string &File) const
	Export large object's contents to a local file. More...
Identity comparisons
These operators compare the object identifiers of large objects. This has nothing to do with the objects' actual contents; use them only for keeping track of containers of references to large objects and such.
bool	operator== (const largeobject &other) const
	Compare object identities. More...
bool	operator!= (const largeobject &other) const
	Compare object identities. More...
bool	operator<= (const largeobject &other) const
	Compare object identities. More...
bool	operator>= (const largeobject &other) const
	Compare object identities. More...
bool	operator< (const largeobject &other) const
	Compare object identities. More...
bool	operator> (const largeobject &other) const
	Compare object identities. More...

Protected Member Functions
PGSTD::string	Reason (int err) const

Static Protected Member Functions
static internal::pq::PGconn *PQXX_PURE	RawConnection (const dbtransaction &T)

Private Attributes
oid	m_ID

Detailed Description

Identity of a large object.

This class encapsulates the identity of a large object. To access the contents of the object, create a largeobjectaccess, a largeobject_streambuf, or an ilostream, an olostream or a lostream around the largeobject.

A largeobject must be accessed only from within a backend transaction, but the object's identity remains valid as long as the object exists.

Member Typedef Documentation

typedef long pqxx::largeobject::size_type

Constructor & Destructor Documentation

pqxx::largeobject::largeobject

(

)

throw ()

Refer to a nonexistent large object (similar to what a null pointer does)

pqxx::largeobject::largeobject ( dbtransaction &  T )

explicit

Create new large object.

Parameters

T	Backend transaction in which the object is to be created

pqxx::largeobject::largeobject ( oid  O ) throw ()

inlineexplicit

Wrap object with given oid.

Convert combination of a transaction and object identifier into a large object identity. Does not affect the database.

Parameters

O	Object identifier for the given object

pqxx::largeobject::largeobject	(	dbtransaction &	T,
		const PGSTD::string &	File
	)

Import large object from a local file.

Creates a large object containing the data found in the given file.

Parameters

T	Backend transaction in which the large object is to be created
File	A filename on the client program's filesystem

pqxx::largeobject::largeobject

(

const largeobjectaccess &

O

)

throw ()

Take identity of an opened large object.

Copy identity of already opened large object. Note that this may be done as an implicit conversion.

Parameters

O	Already opened large object to copy identity from

Member Function Documentation

oid pqxx::largeobject::id ( ) const throw ()

inline

Object identifier.

The number returned by this function identifies the large object in the database we're connected to (or oid_none is returned if we refer to the null object).

bool pqxx::largeobject::operator!= ( const largeobject &  other ) const

inline

Compare object identities.

Warning

Only valid between large objects in the same database.

bool pqxx::largeobject::operator< ( const largeobject &  other ) const

inline

Compare object identities.

Warning

Only valid between large objects in the same database.

bool pqxx::largeobject::operator<= ( const largeobject &  other ) const

inline

Compare object identities.

Warning

Only valid between large objects in the same database.

bool pqxx::largeobject::operator== ( const largeobject &  other ) const

inline

Compare object identities.

Warning

Only valid between large objects in the same database.

bool pqxx::largeobject::operator> ( const largeobject &  other ) const

inline

Compare object identities.

Warning

Only valid between large objects in the same database.

bool pqxx::largeobject::operator>= ( const largeobject &  other ) const

inline

Compare object identities.

Warning

Only valid between large objects in the same database.

static internal::pq::PGconn* PQXX_PURE pqxx::largeobject::RawConnection ( const dbtransaction &  T )

staticprotected

Referenced by pqxx::largeobjectaccess::RawConnection().

Here is the caller graph for this function:

PGSTD::string pqxx::largeobject::Reason ( int  err ) const

protected

void pqxx::largeobject::remove

(

dbtransaction &

T

)

const

Delete large object from database.

Unlike its low-level equivalent cunlink, this will throw an exception if deletion fails.

Parameters

T	Transaction in which the object is to be deleted

void pqxx::largeobject::to_file	(	dbtransaction &	T,
		const PGSTD::string &	File
	)		const

Export large object's contents to a local file.

Writes the data stored in the large object to the given file.

Parameters

T	Transaction in which the object is to be accessed
File	A filename on the client's filesystem

Referenced by pqxx::largeobjectaccess::to_file().

Here is the caller graph for this function:

Member Data Documentation

oid pqxx::largeobject::m_ID

private

---

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

• /usr/include/pqxx/largeobject.hxx