Identity of a large object. More...
#include <largeobject.hxx>
Public Types | |
| using | size_type = large_object_size_type |
Public Member Functions | |
| largeobject () noexcept=default | |
| largeobject (dbtransaction &t) | |
| Create new large object. More... | |
| largeobject (oid o) noexcept | |
| Wrap object with given oid. More... | |
| largeobject (dbtransaction &t, std::string_view file) | |
| Import large object from a local file. More... | |
| largeobject (largeobjectaccess const &o) noexcept | |
| Take identity of an opened large object. More... | |
| oid | id () const noexcept |
| Object identifier. 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== (largeobject const &other) const |
| Compare object identities. More... | |
| bool | operator!= (largeobject const &other) const |
| Compare object identities. More... | |
| bool | operator<= (largeobject const &other) const |
| Compare object identities. More... | |
| bool | operator>= (largeobject const &other) const |
| Compare object identities. More... | |
| bool | operator< (largeobject const &other) const |
| Compare object identities. More... | |
| bool | operator> (largeobject const &other) const |
| Compare object identities. More... | |
| void | to_file (dbtransaction &t, std::string_view file) const |
| Export large object's contents to a local file. More... | |
| void | remove (dbtransaction &t) const |
| Delete large object from database. More... | |
| static PQXX_PURE internal::pq::PGconn * | raw_connection (dbtransaction const &T) |
| std::string | reason (connection const &, int err) const |
Detailed Description
Identity of a large object.
- Deprecated:
- Use the blob class instead.
Encapsulates the identity of a large object.
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
◆ size_type
Constructor & Destructor Documentation
◆ largeobject() [1/5]
|
defaultnoexcept |
Refer to a nonexistent large object (similar to what a null pointer does).
◆ largeobject() [2/5]
|
explicit |
Create new large object.
- Parameters
-
t Backend transaction in which the object is to be created.
References pqxx::transaction_base::conn(), pqxx::oid_none, and reason().
◆ largeobject() [3/5]
|
explicitnoexcept |
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.
◆ largeobject() [4/5]
| PQXX_COLD pqxx::largeobject::largeobject | ( | dbtransaction & | t, |
| std::string_view | 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.
References pqxx::transaction_base::conn(), pqxx::oid_none, and reason().
◆ largeobject() [5/5]
|
noexcept |
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
◆ id()
|
noexcept |
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).
◆ operator!=()
| bool pqxx::largeobject::operator!= | ( | largeobject const & | other | ) | const |
Compare object identities.
- Warning
- Only valid between large objects in the same database.
◆ operator<()
| bool pqxx::largeobject::operator< | ( | largeobject const & | other | ) | const |
Compare object identities.
- Warning
- Only valid between large objects in the same database.
◆ operator<=()
| bool pqxx::largeobject::operator<= | ( | largeobject const & | other | ) | const |
Compare object identities.
- Warning
- Only valid between large objects in the same database.
◆ operator==()
| bool pqxx::largeobject::operator== | ( | largeobject const & | other | ) | const |
Compare object identities.
- Warning
- Only valid between large objects in the same database.
◆ operator>()
| bool pqxx::largeobject::operator> | ( | largeobject const & | other | ) | const |
Compare object identities.
- Warning
- Only valid between large objects in the same database.
◆ operator>=()
| bool pqxx::largeobject::operator>= | ( | largeobject const & | other | ) | const |
Compare object identities.
- Warning
- Only valid between large objects in the same database.
◆ raw_connection()
|
staticprotected |
References pqxx::transaction_base::conn().
Referenced by pqxx::largeobjectaccess::operator=().
◆ reason()
|
protected |
Referenced by largeobject().
◆ remove()
| void PQXX_COLD 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
References pqxx::oid_none.
◆ to_file()
| void PQXX_COLD pqxx::largeobject::to_file | ( | dbtransaction & | t, |
| std::string_view | 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
References pqxx::transaction_base::conn(), and pqxx::oid_none.
Referenced by pqxx::largeobjectaccess::to_file().
The documentation for this class was generated from the following files:
- largeobject.hxx
- largeobject.cxx
