Indexed cells represent one or more cells that are covered by an index. More...

#include <indexed_cells.h>

Public Member Functions
	Indexed_cells (const unsigned char *mysql_search_cells, uint16_t mysql_search_cells_length, const Index &index)
	Construct from a MySQL indexed cells (eg index_read() input buffer). More...

	Indexed_cells (const unsigned char *mysql_row, const Index &index)
	Construct from a mysql row. More...

	Indexed_cells (const Row &row, const Index &index)
	Construct from a row in a table. More...

Storage::Element *	row () const
	Get the row of these indexed cells. More...

void	export_row_to_mysql (const Columns &columns, unsigned char *mysql_row, size_t mysql_row_length) const
	Export the row of these indexed cells in the mysql row format (write_row()). More...

size_t	number_of_cells () const
	Get the number of indexed cells. More...

void	number_of_cells (size_t n)
	Set the number of indexed cells. More...

Cell	cell (size_t i, const Index &index) const
	Get a given indexed cell. More...

int	compare (const Indexed_cells &rhs, const Index &index) const
	Compare to another indexed cells object. More...

Private Types
enum class	Data_location : uint8_t { MYSQL_BUF_INDEX_READ , MYSQL_BUF_WRITE_ROW , ROW }
	Enum that designates where the actual user data is stored. More...

Private Member Functions
Cell	cell_from_mysql_buf_index_read (size_t i, const Index &index) const
	Derive the Nth cell if `m_data_location == Data_location::MYSQL_BUF_INDEX_READ`. More...

Static Private Member Functions
static Cell	cell_from_row (size_t i, const Index &index, const Row &row)
	Generate a cell from a `temptable::Row` object with a possibly reduced length, if a prefix index is used. More...

Private Attributes
Data_location	m_data_location
	Flag indicating whether we are interpreting MySQL buffer or we have references to a `temptable::Row` object. More...

uint8_t	m_number_of_cells
	Number of cells that are indexed. More...

uint16_t	m_length
	MySQL search cells' length, used only when `m_data_location == MYSQL_BUF_INDEX_READ`. More...

union {
const unsigned char * m_mysql_buf
	Pointer to one of: More...

const Row * m_row
	Pointer to the row, used when m_data_location == ROW. More...

};
	Save space by putting the members in a union. More...

Detailed Description

Indexed cells represent one or more cells that are covered by an index.

Member Enumeration Documentation

◆ Data_location

enum class temptable::Indexed_cells::Data_location : uint8_t

strongprivate

Enum that designates where the actual user data is stored.

Enumerator
MYSQL_BUF_INDEX_READ	The data is in a MySQL buffer in index_read() input format (MySQL search cells).
MYSQL_BUF_WRITE_ROW	The data is in a MySQL buffer in write_row() format (MySQL row).
ROW	The data is in `temptable::Row`.

Constructor & Destructor Documentation

◆ Indexed_cells() [1/3]

temptable::Indexed_cells::Indexed_cells	(	const unsigned char *	mysql_search_cells,
		uint16_t	mysql_search_cells_length,
		const Index &	index
	)

Construct from a MySQL indexed cells (eg index_read() input buffer).

Parameters

[in]	mysql_search_cells	Search cells in "index_read() input" format. These must remain valid during the lifetime of the created `Indexed_cells` object.
[in]	mysql_search_cells_length	The length of `mysql_search_cells` in bytes.
[in]	index	MySQL index, used for querying metadata.

◆ Indexed_cells() [2/3]

temptable::Indexed_cells::Indexed_cells	(	const unsigned char *	mysql_row,
		const Index &	index
	)

Construct from a mysql row.

The row must remain valid during the lifetime of the created Indexed_cells object.

Parameters

[in]	mysql_row	MySQL row.
[in]	index	MySQL index whose cells this `Indexed_cells` represents.

◆ Indexed_cells() [3/3]

temptable::Indexed_cells::Indexed_cells	(	const Row &	row,
		const Index &	index
	)

Construct from a row in a table.

The row must remain valid during the lifetime of the created Indexed_cells object.

Parameters

[in]	row	Row from which to create the indexed cells.
[in]	index	MySQL index, used for querying metadata.

Member Function Documentation

◆ cell()

Cell temptable::Indexed_cells::cell	(	size_t	i,
		const Index &	index
	)		const

Get a given indexed cell.

Returns: cell

Parameters

[in]	i	Index of the cell within the indexed cells, must be in [0, number_of_cells()).
[in]	index	Index to which the current objects belongs, used for querying metadata.

◆ cell_from_mysql_buf_index_read()

Cell temptable::Indexed_cells::cell_from_mysql_buf_index_read	(	size_t	i,
		const Index &	index
	)		const

private

Derive the Nth cell if m_data_location == Data_location::MYSQL_BUF_INDEX_READ.

Returns: Nth cell

Parameters

[in]	i	Index of the cell within the indexed cells, must be in [0, number_of_cells()).
[in]	index	Index, for querying metadata via the MySQL index.

◆ cell_from_row()

Cell temptable::Indexed_cells::cell_from_row	(	size_t	i,
		const Index &	index,
		const Row &	row
	)

staticprivate

Generate a cell from a temptable::Row object with a possibly reduced length, if a prefix index is used.

Parameters

[in]	i	Indexed cell number in the index. E.g. if we have a row (a, b, c, d) and an index on (b, c) and we want the cell `c`, then this will be 1.
[in]	index	Index to which the current objects belongs, used for querying metadata.
[in]	row	Row that contains the data.

◆ compare()

int temptable::Indexed_cells::compare	(	const Indexed_cells &	rhs,
		const Index &	index
	)		const

Compare to another indexed cells object.

Each cell is compared individually until a differing cells are found. If the compared objects contain different number of cells and all cells are equal up to the smaller object, then the objects are considered equal. E.g. (10, 15) == (10, 15, 23).

Return values

<0	if this < rhs
0	if this == rhs
>0	if this > rhs

Parameters

[in]	rhs	Indexed cells to compare with the current object.
[in]	index	Index, used for querying metadata.

◆ export_row_to_mysql()

void temptable::Indexed_cells::export_row_to_mysql	(	const Columns &	columns,
		unsigned char *	mysql_row,
		size_t	mysql_row_length
	)		const

inline

Export the row of these indexed cells in the mysql row format (write_row()).

As with the row() method, this one does not make sense and must not be called if the current Indexed_cells object has been created from MySQL search cells.

Parameters

[in]	columns	Metadata for the columns that constitute the exported row.
[out]	mysql_row	Buffer to write the MySQL row into.
[in]	mysql_row_length	Presumed length of the mysql row in bytes.

◆ number_of_cells() [1/2]

size_t temptable::Indexed_cells::number_of_cells ( ) const

inline

Get the number of indexed cells.

Returns: number of indexed cells

◆ number_of_cells() [2/2]

void temptable::Indexed_cells::number_of_cells ( size_t n )

inline

Set the number of indexed cells.

It only makes sense to reduce the number in order to compare less cells for the purposes of prefix search. We treat (10) == (10, 20).

◆ row()

Storage::Element * temptable::Indexed_cells::row ( ) const

inline

Get the row of these indexed cells.

There is no row if this Indexed_cells object has been created from a MySQL search cells (Handler::index_read() input), so this method must not be called in this case.

Returns: row, an element of Table::m_rows

Member Data Documentation

◆

union { ... } temptable::Indexed_cells::@202

Save space by putting the members in a union.

Exactly one of those is used.

◆ m_data_location

Data_location temptable::Indexed_cells::m_data_location

private

Flag indicating whether we are interpreting MySQL buffer or we have references to a temptable::Row object.

◆ m_length

uint16_t temptable::Indexed_cells::m_length

private

MySQL search cells' length, used only when m_data_location == MYSQL_BUF_INDEX_READ.

◆ m_mysql_buf

const unsigned char* temptable::Indexed_cells::m_mysql_buf

Pointer to one of:

MySQL search cells buffer (index_read() input format) used when m_data_location == MYSQL_BUF_INDEX_READ or
MySQL row in write_row() format used when m_data_location == MYSQL_BUF_WRITE_ROW.

◆ m_number_of_cells

uint8_t temptable::Indexed_cells::m_number_of_cells

private

Number of cells that are indexed.

◆ m_row

const Row* temptable::Indexed_cells::m_row

Pointer to the row, used when m_data_location == ROW.

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

storage/temptable/include/temptable/indexed_cells.h
storage/temptable/src/indexed_cells.cc

Public Member Functions

Private Types

Private Member Functions

Static Private Member Functions

Private Attributes

Detailed Description

Member Enumeration Documentation

◆ Data_location

Constructor & Destructor Documentation

◆ Indexed_cells() [1/3]

◆ Indexed_cells() [2/3]

◆ Indexed_cells() [3/3]

Member Function Documentation

◆ cell()

◆ cell_from_mysql_buf_index_read()

◆ cell_from_row()

◆ compare()

◆ export_row_to_mysql()

◆ number_of_cells() [1/2]

◆ number_of_cells() [2/2]

◆ row()

Member Data Documentation

◆

◆ m_data_location

◆ m_length

◆ m_mysql_buf

◆ m_number_of_cells

◆ m_row