A row representation. More...

#include <row.h>

Public Member Functions
	Row (const unsigned char mysql_row, Allocator< uint8_t > allocator)

	Row (const Row &)=delete
	Copy constructing is disabled because it is too expensive. More...

Row &	operator= (const Row &)=delete
	Copy assignment is disabled because it is too expensive. More...

	Row (Row &&other)=delete
	Move constructor. More...

Row &	operator= (Row &&rhs)=delete
	Move assignment. More...

	~Row ()
	Destructor. More...

Cell	cell (const Column &column, size_t i) const
	Get a given cell. More...

Result	copy_to_own_memory (const Columns &columns, size_t mysql_row_length) const
	Copy the user data to an own buffer (convert from write_row() format). More...

void	copy_to_mysql_row (const Columns &columns, unsigned char *mysql_row, size_t mysql_row_length) const
	Copy the row in a MySQL buffer (convert to write_row() format). More...

Static Public Member Functions
static void	swap (Row &r1, Row &r2)
	Swaps contents of two rows. More...

static int	compare (const Row &lhs, const Row &rhs, const Columns &columns, Field **mysql_fields)
	Compare to another row. More...

Private Member Functions
Cell *	cells () const
	Get a pointer to the cells array. More...

Cell	cell_in_row (size_t i) const
	Get a given cell. More...

Cell	cell_in_mysql_memory (const Column &column) const
	Get a given cell. More...

size_t	buf_length () const
	Derives the length of the buffer pointed to by `m_ptr` in bytes (when `m_data_is_in_mysql_memory` is false). More...

Private Attributes
Allocator< uint8_t > *	m_allocator
	Allocator to use when copying from MySQL row to our own memory. More...

bool	m_data_is_in_mysql_memory
	Indicate whether this object is lightweight, with just pointers to the MySQL row buffer or not. More...

unsigned char *	m_ptr
	A pointer to either the mysql row, or our buffer. More...

Detailed Description

A row representation.

A row consists of multiple cells. A row is created from a handler row (in write_row() format) and initially it refers the data in the provided handler row - without copying any user data. Nevertheless such a lightweight row can be used in the same way as a row that has copied the user data and owns it.

Constructor & Destructor Documentation

◆ Row() [1/3]

temptable::Row::Row	(	const unsigned char *	mysql_row,
		Allocator< uint8_t > *	allocator
	)

inlineexplicit

◆ Row() [2/3]

temptable::Row::Row ( const Row & )

delete

Copy constructing is disabled because it is too expensive.

◆ Row() [3/3]

temptable::Row::Row ( Row && other )

delete

Move constructor.

other is undefined after this call.

◆ ~Row()

temptable::Row::~Row ( )

inline

Destructor.

Member Function Documentation

◆ buf_length()

size_t temptable::Row::buf_length ( ) const

inlineprivate

Derives the length of the buffer pointed to by m_ptr in bytes (when m_data_is_in_mysql_memory is false).

Returns: buffer length

◆ cell()

Cell temptable::Row::cell	(	const Column &	column,
		size_t	i
	)		const

inline

Get a given cell.

The cell contains pointers inside the row, so its lifetime should not be longer than the row.

Returns: a cell from the row.

Parameters

[in]	column	Column that corresponds to this cell.
[in]	i	The index of the cell to fetch (must be < number_of_cells()).

◆ cell_in_mysql_memory()

Cell temptable::Row::cell_in_mysql_memory ( const Column & column ) const

inlineprivate

Get a given cell.

The cell contains pointers inside the row, so the returned cell's lifetime should not be longer than the row.

Returns: a cell from the row.

Parameters

[in] column Column that corresponds to this cell.

◆ cell_in_row()

Cell temptable::Row::cell_in_row ( size_t i ) const

inlineprivate

Get a given cell.

The cell contains pointers inside the row, so its lifetime should not be longer than the row.

Returns: a cell from the row.

Parameters

[in] i The index of the cell to fetch (must be < number_of_cells()).

◆ cells()

Cell * temptable::Row::cells ( ) const

inlineprivate

Get a pointer to the cells array.

Only defined if m_data_is_in_mysql_memory is false.

Returns: cells array

◆ compare()

int temptable::Row::compare	(	const Row &	lhs,
		const Row &	rhs,
		const Columns &	columns,
		Field **	mysql_fields
	)

static

Compare to another row.

Used by Table::update() and Table::remove() to double check that the row which is passed as "old row" indeed equals to the row pointed to by the specified position.

Return values

<0	if lhs < rhs
0	if lhs == rhs
>0	if lhs > rhs

Parameters

[in]	lhs	First row to compare.
[in]	rhs	Second row to compare.
[in]	columns	Columns that constitute `this` and in `rhs`.
[in]	mysql_fields	List of MySQL column definitions, used for querying metadata.

◆ copy_to_mysql_row()

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

Copy the row in a MySQL buffer (convert to write_row() format).

Parameters

[in]	columns	Metadata for the columns that constitute this row.
[out]	mysql_row	Destination buffer to copy the row to.
[in]	mysql_row_length	Presumed length of the mysql row in bytes.

◆ copy_to_own_memory()

Result temptable::Row::copy_to_own_memory	(	const Columns &	columns,
		size_t	mysql_row_length
	)		const

Copy the user data to an own buffer (convert from write_row() format).

Returns: Result:OK or other Result::* error code

Parameters

[in]	columns	Metadata for the columns that constitute this row.
[in]	mysql_row_length	Length of the mysql row in bytes (m_ptr).

◆ operator=() [1/2]

Row & temptable::Row::operator= ( const Row & )

delete

Copy assignment is disabled because it is too expensive.

◆ operator=() [2/2]

Row & temptable::Row::operator= ( Row && rhs )

delete

Move assignment.

rhs is undefined after this call.

◆ swap()

void temptable::Row::swap	(	Row &	r1,
		Row &	r2
	)

inlinestatic

Swaps contents of two rows.

Parameters

[in,out]	r1	First row to swap.
[in,out]	r2	Seconds row to swap.

Member Data Documentation

◆ m_allocator

Allocator<uint8_t>* temptable::Row::m_allocator

private

Allocator to use when copying from MySQL row to our own memory.

◆ m_data_is_in_mysql_memory

bool temptable::Row::m_data_is_in_mysql_memory

mutableprivate

Indicate whether this object is lightweight, with just pointers to the MySQL row buffer or not.

◆ m_ptr

unsigned char* temptable::Row::m_ptr

mutableprivate

A pointer to either the mysql row, or our buffer.

If

m_data_is_in_mysql_memory is true, then this points to a buffer in mysql write_row() format, not owned by the current Row object;
m_data_is_in_mysql_memory is false, then this points a our own buffer that holds the cells and the user data. Its structure is: [0, A = sizeof(size_t)): buffer length [A, B = A + number_of_cells * sizeof(Cell)): cells array [B, B + sum(user data length for each cell)): user data of the cells

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

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

Public Member Functions

Static Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ Row() [1/3]

◆ Row() [2/3]

◆ Row() [3/3]

◆ ~Row()

Member Function Documentation

◆ buf_length()

◆ cell()

◆ cell_in_mysql_memory()

◆ cell_in_row()

◆ cells()

◆ compare()

◆ copy_to_mysql_row()

◆ copy_to_own_memory()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ swap()

Member Data Documentation

◆ m_allocator

◆ m_data_is_in_mysql_memory

◆ m_ptr