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Ionflux::Tools::BufferedTable Class Reference
[Database interface]

Buffered database table. More...

#include <BufferedTable.hpp>

Inheritance diagram for Ionflux::Tools::BufferedTable:

[legend]Collaboration diagram for Ionflux::Tools::BufferedTable:

[legend]List of all members.

Public Member Functions
	BufferedTable ()
	Constructor.
	BufferedTable (unsigned int initBlockSize)
	Constructor.
	BufferedTable (Ionflux::Tools::Database *initDatabase)
	Constructor.
	BufferedTable (Ionflux::Tools::Database *initDatabase, unsigned int initBlockSize)
	Constructor.
	BufferedTable (Ionflux::Tools::Database *initDatabase, unsigned int initBlockSize, const std::string &initTable, const std::string &initKeyField, const std::vector< std::string > &initFields)
	Constructor.
	BufferedTable (Ionflux::Tools::Database *initDatabase, unsigned int initBlockSize, const std::string &initTable, const std::string &initKeyField, const std::vector< std::string > &initFields, const std::string &initOrigin)
	Constructor.
virtual	~BufferedTable ()
	Destructor.
virtual void	setConfig (Ionflux::Tools::Node &newConfig)
	Set configuration.
virtual void	setDatabase (Ionflux::Tools::Database *newDatabase)
	Set source database.
virtual Ionflux::Tools::Database *	getDatabase ()
	Get source database.
virtual bool	validateTable ()
	Validate database table.
virtual Ionflux::Tools::Node *	getRecord (int recIndex)
	Get record.
virtual Ionflux::Tools::Node *	operator[] (int recIndex)
	Get record.
virtual Ionflux::Tools::Node *	getCurrentRecord ()
	Get current record.
virtual Ionflux::Tools::Node *	getNextRecord ()
	Get next record.
virtual Ionflux::Tools::Node *	getPrevRecord ()
	Get previous record.
virtual int	getTableOffset (const std::string &key)
	Get key table offset.
virtual std::string	getKey (const std::string &key, int recOffset)
	Get key.
virtual std::string	getKey (int recIndex)
	Get key by index.
virtual std::string	fetchKey (unsigned int offset)
	Get key from database table.
virtual unsigned int	getNumRecs ()
	Get number of records.
virtual unsigned int	getFieldIndex (const std::string &fieldName)
	Get field index.
virtual void	refresh ()
	Refresh buffer.
virtual void	clearBlocks ()
	Clear buffer blocks.
virtual void	clear ()
	Clear buffer.
virtual Ionflux::Tools::Reporter &	getLog ()
	Get Console output/logging facility.
virtual void	setOrigin (unsigned int offset)
	Set key of the record with index pointer zero.
virtual void	setCurrentRecord (const std::string &newKey)
	Set current record.
virtual void	setBlockSize (unsigned int newBlockSize)
	Set buffer block size.
virtual void	setOrigin (const std::string &newOrigin)
	Set key of the record with index pointer zero.
virtual void	setTable (const std::string &newTable)
	Set source database table name.
virtual void	setKeyField (const std::string &newKeyField)
	Set name of the key field of the source database table.
virtual void	setFields (const std::vector< std::string > &newFields)
	Set names of fields to be included in each record.
virtual void	setCurrentIndex (int newCurrentIndex)
	Set index of current record.
virtual void	setCreateTemplate (const std::string &newCreateTemplate)
	Set create template.
virtual void	setCreateTemplateFile (const std::string &newCreateTemplateFile)
	Set create template file name.
virtual unsigned int	getBlockSize () const
	Get buffer block size.
virtual std::string	getOrigin () const
	Get key of the record with index pointer zero.
virtual std::string	getTable () const
	Get source database table name.
virtual std::string	getKeyField () const
	Get name of the key field of the source database table.
virtual std::vector< std::string >	getFields () const
	Get names of fields to be included in each record.
virtual int	getCurrentIndex () const
	Get index of current record.
virtual std::string	getCreateTemplate () const
	Get create template.
virtual std::string	getCreateTemplateFile () const
	Get create template file name.
Static Public Attributes
static const unsigned int	DEFAULT_BLOCK_SIZE = 50
	Default buffering block size.
Protected Member Functions
virtual void	cycleForward ()
	Cycle buffers (forward).
virtual void	cycleBackward ()
	Cycle buffers (backward).
virtual void	updateIndices ()
	Update indices.
virtual void	initBlock (Ionflux::Tools::Node *target, const std::string &fromKey, bool invert=false)
	Initialize buffer block.
virtual int	getBlockStartOffset (const std::string &key)
	Get block start offset.
Protected Attributes
Ionflux::Tools::Reporter	log
	Console output/logging.
Ionflux::Tools::ObjectPool	pool
	Object allocation pool.
Ionflux::Tools::Database *	database
	Source database.
Ionflux::Tools::Node *	prevBlock
	Previous block.
Ionflux::Tools::Node *	currentBlock
	Current block.
Ionflux::Tools::Node *	nextBlock
	Next block.
int	currentOffset
	Index of the first record of the current block.
std::map< std::string, unsigned int >	offsetIndex
	Key/offset index.
std::vector< std::string >	keyIndex
	Offset/key index.
unsigned int	blockSize
	Buffer block size.
std::string	origin
	Key of the record with index pointer zero.
std::string	table
	Source database table name.
std::string	keyField
	Name of the key field of the source database table.
std::vector< std::string >	fields
	Names of fields to be included in each record.
int	currentIndex
	Index of current record.
std::string	createTemplate
	Create template.
std::string	createTemplateFile
	Create template file name.
Ionflux::Tools::Node	config
	Buffered table configuration node.

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Detailed Description

Buffered database table.

A buffered table providing access to records which are stored in a database table. The table buffer allows for the efficient sequential retrieval of records from the database, where the order of records is defined by a specified key field. This is achieved by fetching a block (or page) of records on each database query. Records from the blocks loaded into memory may then be accessed sequentially. A new block is fetched from the database automatically whenever the current index pointer goes out of the scope of a block.

Note:

The buffered table also allows random access, however, this does not have any advantages in efficiency unless the random accesses occur within order of the block size.

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Constructor & Destructor Documentation

Ionflux::Tools::BufferedTable::BufferedTable (   )

Constructor. Construct new BufferedTable object.

Ionflux::Tools::BufferedTable::BufferedTable (  unsigned int  initBlockSize  )

Constructor. Construct new BufferedTable object. Parameters: initBlockSize  Buffering block size.

Ionflux::Tools::BufferedTable::BufferedTable (  Ionflux::Tools::Database *  initDatabase  )

Constructor. Construct new BufferedTable object. Parameters: initDatabase  Source database.

Ionflux::Tools::BufferedTable::BufferedTable (  Ionflux::Tools::Database *  initDatabase, unsigned int  initBlockSize )

Constructor. Construct new BufferedTable object. Parameters: initDatabase  Source database. initBlockSize  Buffering block size.

Ionflux::Tools::BufferedTable::BufferedTable (  Ionflux::Tools::Database *  initDatabase, unsigned int  initBlockSize, const std::string &  initTable, const std::string &  initKeyField, const std::vector< std::string > &  initFields )

Constructor. Construct new BufferedTable object. Parameters: initDatabase  Source database. initBlockSize  Buffering block size. initTable  Source database table name. initKeyField  Name of the key field of the source database table. initFields  Names of fields to be included in each record.

Ionflux::Tools::BufferedTable::BufferedTable (  Ionflux::Tools::Database *  initDatabase, unsigned int  initBlockSize, const std::string &  initTable, const std::string &  initKeyField, const std::vector< std::string > &  initFields, const std::string &  initOrigin )

Constructor. Construct new BufferedTable object. Parameters: initDatabase  Source database. initBlockSize  Buffering block size. initTable  Source database table name. initKeyField  Name of the key field of the source database table. initFields  Names of fields to be included in each record. initOrigin  Key of the record with index pointer zero.

Ionflux::Tools::BufferedTable::~BufferedTable (   )  [virtual]

Destructor. Destruct BufferedTable object.

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Member Function Documentation

void Ionflux::Tools::BufferedTable::clear (   )  [virtual]

Clear buffer. Clear all records from the buffer.

void Ionflux::Tools::BufferedTable::clearBlocks (   )  [virtual]

Clear buffer blocks. Clear all records from the buffer blocks. Note: While this function will clear all data from the buffer, it will not touch any of the other internal state (unlike clear()). See also: clear

void Ionflux::Tools::BufferedTable::cycleBackward (   )  [protected, virtual]

Cycle buffers (backward). Cycle the buffer blocks backward. Note: This effectively discards the next block, sets the next block to the current block, the current block to the previous block end empties the previous block.

void Ionflux::Tools::BufferedTable::cycleForward (   )  [protected, virtual]

Cycle buffers (forward). Cycle the buffer blocks forward. Note: This effectively discards the previous block, sets the previous block to the current block, the current block to the next block end empties the next block.

std::string Ionflux::Tools::BufferedTable::fetchKey (  unsigned int  offset  )  [virtual]

Get key from database table. Get the key of the record with the specified offset from the start of the database table. See also: getKey Parameters: offset  Record offset. Returns: Key of record with specified offset, or an empty string if record does not exist..

unsigned int Ionflux::Tools::BufferedTable::getBlockSize (   )  const [virtual]

Get buffer block size. Returns: Current value of buffer block size.

int Ionflux::Tools::BufferedTable::getBlockStartOffset (  const std::string &  key  )  [protected, virtual]

Get block start offset. Get the offset of the start of the data block which contains the specified key, relative to the specified key. Note: A data block is a block of data in the source database table of buffer block size, with the first block aligned to the start of the table. The data block that contains a certain key may be different from the buffer block that contains that same key. Data and buffer blocks can contain the same data only if the buffer block boundaries are aligned to the data block boundaries. Parameters: key  Key. Returns: Block start offset.

std::string Ionflux::Tools::BufferedTable::getCreateTemplate (   )  const [virtual]

Get create template. Returns: Current value of create template.

std::string Ionflux::Tools::BufferedTable::getCreateTemplateFile (   )  const [virtual]

Get create template file name. Returns: Current value of create template file name.

int Ionflux::Tools::BufferedTable::getCurrentIndex (   )  const [virtual]

Get index of current record. Returns: Current value of index of current record.

Ionflux::Tools::Node * Ionflux::Tools::BufferedTable::getCurrentRecord (   )  [virtual]

Get current record. Get the current record. Returns: Current record, or null if the record does not exist.

Ionflux::Tools::Database * Ionflux::Tools::BufferedTable::getDatabase (   )  [virtual]

Get source database. Get the source database that will be used for fetching record blocks. Returns: Source database. (The returned object will be referenced).

unsigned int Ionflux::Tools::BufferedTable::getFieldIndex (  const std::string &  fieldName  )  [virtual]

Get field index. Get the index of the specified field. Parameters: fieldName  Field name. Returns: Field index.

std::vector< std::string > Ionflux::Tools::BufferedTable::getFields (   )  const [virtual]

Get names of fields to be included in each record. Returns: Current value of names of fields to be included in each record.

std::string Ionflux::Tools::BufferedTable::getKey (  int  recIndex  )  [virtual]

Get key by index. Get the key of the record with the specified index relative to the origin. See also: fetchKey Parameters: recIndex  Record index. Returns: Key of record with specified index, or an empty string if the record does not exist.

std::string Ionflux::Tools::BufferedTable::getKey (  const std::string &  key, int  recOffset )  [virtual]

Get key. Get the key of the record with the specified offset relative to the record with the specified key. See also: fetchKey Parameters: key  Key. recOffset  Offset of target record. Returns: Key of record with specified offset relative to specified key, or an empty string if the record does not exist.

std::string Ionflux::Tools::BufferedTable::getKeyField (   )  const [virtual]

Get name of the key field of the source database table. Returns: Current value of name of the key field of the source database table.

Ionflux::Tools::Reporter & Ionflux::Tools::BufferedTable::getLog (   )  [virtual]

Get Console output/logging facility. The console output/logging facility used by this object. Returns: Console output/logging facility.

Ionflux::Tools::Node * Ionflux::Tools::BufferedTable::getNextRecord (   )  [virtual]

Get next record. Get the next record. Note: This also makes the next record the current record. Returns: Next record, or null if the record does not exist.

unsigned int Ionflux::Tools::BufferedTable::getNumRecs (   )  [virtual]

Get number of records. Get the number of records in the source database table. Returns: Number of records.

std::string Ionflux::Tools::BufferedTable::getOrigin (   )  const [virtual]

Get key of the record with index pointer zero. Returns: Current value of key of the record with index pointer zero.

Ionflux::Tools::Node * Ionflux::Tools::BufferedTable::getPrevRecord (   )  [virtual]

Get previous record. Get the previous record. Note: This also makes the previous record the current record. Returns: Previous record, or null if the record does not exist.

Ionflux::Tools::Node * Ionflux::Tools::BufferedTable::getRecord (  int  recIndex  )  [virtual]

Get record. Get the record with the specified index. Parameters: recIndex  Record index. Returns: Record with specified index, or null if the record does not exist.

std::string Ionflux::Tools::BufferedTable::getTable (   )  const [virtual]

Get source database table name. Returns: Current value of source database table name.

int Ionflux::Tools::BufferedTable::getTableOffset (  const std::string &  key  )  [virtual]

Get key table offset. Get the database table offset (position relative to the start of the table) of a key. Parameters: key  Key. Returns: Table offset.

void Ionflux::Tools::BufferedTable::initBlock (  Ionflux::Tools::Node *  target, const std::string &  fromKey, bool  invert = false )  [protected, virtual]

Initialize buffer block. Initialize a block of the buffer with records starting from the specified key value. Note: Pass true to invert to initialize a block with records starting from the last record (instead of the first) counting records backwards and result records being aligned to the end of the block (instead of the start of the block). Parameters: target  Where to store the resulting records. fromKey  Key of the first (or last, if invert is true) record of the block. invert  Whether initialization order should be inverted.

Ionflux::Tools::Node * Ionflux::Tools::BufferedTable::operator[] (  int  recIndex  )  [virtual]

Get record. Get the record with the specified index. Parameters: recIndex  Record index. Returns: Record with specified index, or null if the record does not exist.

void Ionflux::Tools::BufferedTable::refresh (   )  [virtual]

Refresh buffer. Refresh the buffer to reflect changes in the database table. Note: This function should always be called after records have been inserted, changed or deleted in the database table. Failing to do this may result in inaccurate buffers or even errors.

void Ionflux::Tools::BufferedTable::setBlockSize (  unsigned int  newBlockSize  )  [virtual]

Set buffer block size. Set new value of buffer block size. Parameters: newBlockSize  New value of buffer block size.

void Ionflux::Tools::BufferedTable::setConfig (  Ionflux::Tools::Node &  newConfig  )  [virtual]

Set configuration. Initialize the configuration of the buffered table from a configuration data node. Parameters: newConfig  Configuration node.

void Ionflux::Tools::BufferedTable::setCreateTemplate (  const std::string &  newCreateTemplate  )  [virtual]

Set create template. Set new value of create template. Parameters: newCreateTemplate  New value of create template.

void Ionflux::Tools::BufferedTable::setCreateTemplateFile (  const std::string &  newCreateTemplateFile  )  [virtual]

Set create template file name. Set new value of create template file name. Parameters: newCreateTemplateFile  New value of create template file name.

void Ionflux::Tools::BufferedTable::setCurrentIndex (  int  newCurrentIndex  )  [virtual]

Set index of current record. Set new value of index of current record. Parameters: newCurrentIndex  New value of index of current record.

void Ionflux::Tools::BufferedTable::setCurrentRecord (  const std::string &  newKey  )  [virtual]

Set current record. Set the current record by key. See also: setCurrentIndex Parameters: newKey  Key of record to be set as current record.

void Ionflux::Tools::BufferedTable::setDatabase (  Ionflux::Tools::Database *  newDatabase  )  [virtual]

Set source database. Set the source database that will be used for fetching record blocks. Parameters: newDatabase  Source database.

void Ionflux::Tools::BufferedTable::setFields (  const std::vector< std::string > &  newFields  )  [virtual]

Set names of fields to be included in each record. Set new value of names of fields to be included in each record. Parameters: newFields  New value of names of fields to be included in each record.

void Ionflux::Tools::BufferedTable::setKeyField (  const std::string &  newKeyField  )  [virtual]

Set name of the key field of the source database table. Set new value of name of the key field of the source database table. Parameters: newKeyField  New value of name of the key field of the source database table.

void Ionflux::Tools::BufferedTable::setOrigin (  const std::string &  newOrigin  )  [virtual]

Set key of the record with index pointer zero. Set new value of key of the record with index pointer zero. Parameters: newOrigin  New value of key of the record with index pointer zero.

void Ionflux::Tools::BufferedTable::setOrigin (  unsigned int  offset  )  [virtual]

Set key of the record with index pointer zero. Set the key of the record with index pointer zero by its offset in the database table. Parameters: offset  Database table offset.

void Ionflux::Tools::BufferedTable::setTable (  const std::string &  newTable  )  [virtual]

Set source database table name. Set new value of source database table name. Parameters: newTable  New value of source database table name.

void Ionflux::Tools::BufferedTable::updateIndices (   )  [protected, virtual]

Update indices. Update the key/offset and offset/key indices.

bool Ionflux::Tools::BufferedTable::validateTable (   )  [virtual]

Validate database table. Validate the existence of the database table. If the table does not exist and a template is set, the table will be created automatically. Returns: true on success, false otherwise.

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Member Data Documentation

unsigned int Ionflux::Tools::BufferedTable::blockSize [protected]

Buffer block size.

Ionflux::Tools::Node Ionflux::Tools::BufferedTable::config [protected]

Buffered table configuration node.

std::string Ionflux::Tools::BufferedTable::createTemplate [protected]

Create template.

std::string Ionflux::Tools::BufferedTable::createTemplateFile [protected]

Create template file name.

Ionflux::Tools::Node* Ionflux::Tools::BufferedTable::currentBlock [protected]

Current block.

int Ionflux::Tools::BufferedTable::currentIndex [protected]

Index of current record.

int Ionflux::Tools::BufferedTable::currentOffset [protected]

Index of the first record of the current block.

Ionflux::Tools::Database* Ionflux::Tools::BufferedTable::database [protected]

Source database.

const unsigned int Ionflux::Tools::BufferedTable::DEFAULT_BLOCK_SIZE = 50 [static]

Default buffering block size.

std::vector<std::string> Ionflux::Tools::BufferedTable::fields [protected]

Names of fields to be included in each record.

std::string Ionflux::Tools::BufferedTable::keyField [protected]

Name of the key field of the source database table.

std::vector<std::string> Ionflux::Tools::BufferedTable::keyIndex [protected]

Offset/key index.

Ionflux::Tools::Reporter Ionflux::Tools::BufferedTable::log [protected]

Console output/logging.

Ionflux::Tools::Node* Ionflux::Tools::BufferedTable::nextBlock [protected]

Next block.

std::map<std::string, unsigned int> Ionflux::Tools::BufferedTable::offsetIndex [protected]

Key/offset index.

std::string Ionflux::Tools::BufferedTable::origin [protected]

Key of the record with index pointer zero.

Ionflux::Tools::ObjectPool Ionflux::Tools::BufferedTable::pool [protected]

Object allocation pool.

Ionflux::Tools::Node* Ionflux::Tools::BufferedTable::prevBlock [protected]

Previous block.

std::string Ionflux::Tools::BufferedTable::table [protected]

Source database table name.

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

• BufferedTable.hpp
• BufferedTable.cpp

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