MySQL NDB Cluster API Developer Guide
This section provides information about the
Undofile
class.
None
The Undofile
class models an NDB Cluster
Disk Data undo file, which stores data used for rolling back
transactions.
Only unindexed column data can be stored on disk. Indexes and indexes columns are always stored in memory.
The following table lists the public methods of this class and the purpose or use of each method:
Table 2.81 Undofile class methods and descriptions
Name | Description |
---|---|
Undofile() |
Class constructor |
~Undofile() |
Virtual destructor |
getFileNo() |
Removed in NDB 7.5.0 (Bug #47960, Bug #11756088) |
getLogfileGroup() |
Gets the name of the log file group to which the undo file belongs |
getLogfileGroupId() |
Gets the ID of the log file group to which the undo file belongs |
getNode() |
Removed in NDB 7.5.0 (Bug #47960, Bug #11756088) |
getObjectId() |
Gets the undo file's object ID |
getObjectStatus() |
Gets the undo file's Status |
getObjectVersion() |
Gets the undo file's object version |
getPath() |
Gets the undo file's file system path |
getSize() |
Gets the size of the undo file |
setLogfileGroup() |
Sets the undo file's log file group using the name of the log file
group or a reference to the corresponding
LogfileGroup object |
setNode() |
Removed in NDB 7.5.0 (Bug #47960, Bug #11756088) |
setPath() |
Sets the file system path for the undo file |
setSize() |
Sets the undo file's size |
The Undofile
class defines no public
types.
The class constructor can be used to create a new
Undofile
instance, or to
copy an existing one.
Create a new instance:
Undofile ( void )
Copy constructor:
Undofile
(
const Undofile& undoFile
)
New instance: None. The copy
constructor takes a single argument—a reference to the
Undofile
object to be
copied.
An Undofile
object.
Destructor.
The class defines a virtual destructor which takes no arguments
and has the return type void
.
This method did not work as intended, and was removed in NDB 7.5.0 (Bug #47960, Bug #11756088).
Uint32 getFileNo ( void ) const
None.
The number of the undo file, as an unsigned 32-bit integer.
This method retrieves the name of the log file group to which the undo file belongs.
const char* getLogfileGroup ( void ) const
None.
The name of the log file group, a string value (as a character pointer).
This method retrieves the ID of the log file group to which the undo file belongs.
It is also possible to obtain the name of the log file group directly. See Undofile::getLogfileGroup()
Uint32 getLogfileGroupId ( void ) const
None.
The ID of the log file group, as an unsigned 32-bit integer.
This method did not work as intended, and was removed in NDB 7.5.0 (Bug #47960, Bug #11756088).
Uint32 getNode ( void ) const
None.
The node ID, as an unsigned 32-bit integer.
This method retrieves the undo file's object ID.
virtual int getObjectId ( void ) const
None.
The object ID, as an integer.
This method is used to retrieve the object status of an undo file.
virtual Object::Status getObjectStatus ( void ) const
None.
An Object::Status
value.
This method gets the undo file's object version (see NDB Schema Object Versions).
virtual int getObjectVersion ( void ) const
None.
The object version, as an integer.
This method retrieves the path matching the location of the undo file on the data node's file system.
const char* getPath ( void ) const
None.
The file system path, a string (as a character pointer).
This method gets the size of the undo file in bytes.
Uint64 getSize ( void ) const
None.
The size in bytes of the undo file, as an unsigned 64-bit integer.
Given either a name or an object reference to a log file
group, the setLogfileGroup()
method
assigns the undo file to that log file group.
Using a log file group name:
void setLogfileGroup
(
const char* name
)
Using a reference to an instance of
LogfileGroup
:
void setLogfileGroup
(
const class LogfileGroup & logfileGroup
)
The name
of the log file group (a
character pointer), or a reference to a
LogfileGroup
instance.
None.
This method did not work as intended, and was removed in NDB 7.5.0 (Bug #47960, Bug #11756088).
void setNode
(
Uint32 nodeId
)
The nodeId
of the data node where
the undo file is to be placed; this is an unsigned 32-bit
integer.
None.