rec.h File Reference

Record manager. More...

#include "dict0boot.h"
#include "dict0dict.h"

Go to the source code of this file.

Enumerations
enum class	Rec_instant_state { REC_IS_SIMPLE , REC_IS_VERSIONED , REC_IS_INSTANT }
	Instant state of a record. More...
enum	REC_INSERT_STATE {   INSERTED_BEFORE_INSTANT_ADD_OLD_IMPLEMENTATION , INSERTED_AFTER_INSTANT_ADD_OLD_IMPLEMENTATION , INSERTED_AFTER_UPGRADE_BEFORE_INSTANT_ADD_NEW_IMPLEMENTATION , INSERTED_BEFORE_INSTANT_ADD_NEW_IMPLEMENTATION ,   INSERTED_AFTER_INSTANT_ADD_NEW_IMPLEMENTATION , INSERTED_INTO_TABLE_WITH_NO_INSTANT_NO_VERSION , NONE }

Functions
static const ulint *	rec_offs_base (const ulint *offsets)
static ulint *	rec_offs_base (ulint *offsets)
ulint *	rec_get_offsets (const rec_t *rec, const dict_index_t *index, ulint *offsets, ulint n_fields, ut::Location location, mem_heap_t **heap)
	The following function determines the offsets to each field in the record. More...
void	rec_get_offsets_reverse (const byte *extra, const dict_index_t *index, ulint node_ptr, ulint *offsets)
	The following function determines the offsets to each field in the record. More...
static ulint	rec_get_bit_field_1 (const rec_t *rec, ulint offs, ulint mask, ulint shift)
	Gets a bit field from within 1 byte. More...
static uint16_t	rec_get_bit_field_2 (const rec_t *rec, ulint offs, ulint mask, ulint shift)
	Gets a bit field from within 2 bytes. More...
static ulint	rec_get_status (const rec_t *rec)
	The following function retrieves the status bits of a new-style record. More...
bool	rec_info_bits_valid (ulint bits)
	Check if the info bits are valid. More...
static ulint	rec_get_info_bits (const rec_t *rec, ulint comp)
	The following function is used to retrieve the info bits of a record. More...
static ulint	rec_get_info_bits_temp (const rec_t *rec)
	The following function is used to retrieve the info bits of a temporary record. More...
static uint16_t	rec_get_n_fields_old_raw (const rec_t *rec)
	The following function is used to get the number of fields in an old-style record, which is stored in the rec. More...
static uint16_t	rec_get_n_fields_old (const rec_t *rec, const dict_index_t *index)
	The following function is used to get the number of fields in an old-style record. More...
static ulint	rec_get_n_fields (const rec_t *rec, const dict_index_t *index)
	The following function is used to get the number of fields in a record. More...
static bool	rec_n_fields_is_sane (dict_index_t *index, const rec_t *rec, const dtuple_t *entry)
	Confirms the n_fields of the entry is sane with comparing the other record in the same page specified. More...
static ulint	rec_offs_get_n_alloc (const ulint *offsets)
	The following function returns the number of allocated elements for an array of offsets. More...
static void	rec_offs_set_n_alloc (ulint *offsets, ulint n_alloc)
	The following function sets the number of allocated elements for an array of offsets. More...
static void	rec_offs_set_n_fields (ulint *offsets, ulint n_fields)
	The following function sets the number of fields in offsets. More...
static ulint	rec_offs_n_fields (const ulint *offsets)
	The following function returns the number of fields in a record. More...
static uint64_t	rec_get_instant_offset (const dict_index_t *index, ulint n, uint64_t offs)
	Determine the offset of a specified field in the record, when this field is a field added after an instant ADD COLUMN. More...
void	rec_init_offsets (const rec_t *rec, const dict_index_t *index, ulint *offsets)
	The following function determines the offsets to each field in the record. More...
static bool	rec_offs_validate (const rec_t *rec, const dict_index_t *index, const ulint *offsets, const bool check_status=true)
	Validates offsets returned by rec_get_offsets(). More...
static void	rec_offs_make_valid (const rec_t *rec, const dict_index_t *index, ulint *offsets)
	Updates debug data in offsets, in order to avoid bogus rec_offs_validate() failures. More...
bool	rec_offs_cmp (ulint *offsets1, ulint *offsets2)
	Check if the given two record offsets are identical. More...
std::ostream &	rec_offs_print (std::ostream &out, const ulint *offsets)
	Print the record offsets. More...
static bool	rec_get_instant_flag_new (const rec_t *rec)
	The following function tells if a new-style record is instant record. More...
static bool	rec_get_instant_flag_new_temp (const rec_t *rec)
	The following function tells if a new-style temp record is instant record. More...
void	rec_init_fixed_offsets (const dict_index_t *index, ulint *offsets)
	A simplified variant rec_init_offsets(rec, index, offsets) for the case in which the rec contains only fixed-length columns and non-NULL values in them, thus we can compute the offsets without looking at the rec. More...
static bool	rec_new_is_versioned (const rec_t *rec)
	The following function tells if a new-style record is versioned. More...
static bool	rec_old_is_versioned (const rec_t *rec)
	The following function tells if an old-style record is versioned. More...
static bool	rec_new_temp_is_versioned (const rec_t *rec)
	The following function tells if a temporary record is versioned. More...
static uint32_t	rec_get_n_fields_instant (const rec_t *rec, const ulint extra_bytes, uint16_t *length)
	Get the number of fields for one new style leaf page record. More...
static enum REC_INSERT_STATE	get_rec_insert_state (const dict_index_t *index, const rec_t *rec, bool temp)
static enum REC_INSERT_STATE	init_nulls_lens_for_temp_redundant (const dict_index_t *index, const rec_t *rec, uint16_t *n_null, const byte **nulls, const byte **lens, uint16_t &non_default_fields, row_version_t &row_version)
static enum REC_INSERT_STATE	rec_init_null_and_len_temp (const rec_t *rec, const dict_index_t *index, const byte **nulls, const byte **lens, uint16_t *n_null, uint16_t &non_default_fields, row_version_t &row_version)
	Determines the information about null bytes and variable length bytes for a new-style temporary record. More...
static enum REC_INSERT_STATE	rec_init_null_and_len_comp (const rec_t *rec, const dict_index_t *index, const byte **nulls, const byte **lens, uint16_t *n_null, uint16_t &non_default_fields, row_version_t &row_version)
	Determines the information about null bytes and variable length bytes for a new style record. More...
void	rec_init_offsets_comp_ordinary (const rec_t *rec, bool temp, const dict_index_t *index, ulint *offsets)
	Determine the offset to each field in a leaf-page record in ROW_FORMAT=COMPACT. More...
static bool	rec_get_1byte_offs_flag (const rec_t *rec)
	The following function is used to test whether the data offsets in the record are stored in one-byte or two-byte format. More...

Variables
constexpr uint32_t	REC_OFFS_COMPACT = 1U << 31
	NOTE: The functions in this file should only use functions from other files in library. More...
constexpr uint32_t	REC_OFFS_SQL_NULL = 1U << 31
constexpr uint32_t	REC_OFFS_EXTERNAL = 1 << 30
constexpr uint32_t	REC_OFFS_DEFAULT = 1 << 29
constexpr uint32_t	REC_OFFS_DROP = 1 << 28
constexpr uint32_t	REC_OFFS_MASK = REC_OFFS_DROP - 1
constexpr uint32_t	REC_NEW_HEAP_NO = 4
constexpr uint32_t	REC_HEAP_NO_SHIFT = 3
constexpr uint32_t	REC_NEXT = 2
constexpr uint32_t	REC_NEXT_MASK = 0xFFFFUL
constexpr uint32_t	REC_NEXT_SHIFT = 0
constexpr uint32_t	REC_OLD_SHORT = 3
constexpr uint32_t	REC_OLD_SHORT_MASK = 0x1UL
constexpr uint32_t	REC_OLD_SHORT_SHIFT = 0
constexpr uint32_t	REC_OLD_N_FIELDS = 4
constexpr uint32_t	REC_OLD_N_FIELDS_MASK = 0x7FEUL
constexpr uint32_t	REC_OLD_N_FIELDS_SHIFT = 1
constexpr uint32_t	REC_NEW_STATUS = 3
constexpr uint32_t	REC_NEW_STATUS_MASK = 0x7UL
constexpr uint32_t	REC_NEW_STATUS_SHIFT = 0
constexpr uint32_t	REC_OLD_HEAP_NO = 5
constexpr uint32_t	REC_HEAP_NO_MASK = 0xFFF8UL
constexpr uint32_t	REC_OLD_N_OWNED = 6
constexpr uint32_t	REC_NEW_N_OWNED = 5
constexpr uint32_t	REC_N_OWNED_MASK = 0xFUL
constexpr uint32_t	REC_N_OWNED_SHIFT = 0
constexpr uint32_t	REC_OLD_INFO_BITS = 6
constexpr uint32_t	REC_NEW_INFO_BITS = 5
constexpr uint32_t	REC_TMP_INFO_BITS = 1
constexpr uint32_t	REC_INFO_BITS_MASK = 0xF0UL
constexpr uint32_t	REC_INFO_BITS_SHIFT = 0
constexpr uint32_t	REC_INFO_MIN_REC_FLAG = 0x10UL
constexpr uint32_t	REC_INFO_DELETED_FLAG = 0x20UL
	The deleted flag in info bits; when bit is set to 1, it means the record has been delete marked. More...
constexpr uint32_t	REC_INFO_VERSION_FLAG = 0x40UL
constexpr uint32_t	REC_INFO_INSTANT_FLAG = 0x80UL
	The instant ADD COLUMN flag. More...
constexpr uint32_t	REC_N_OLD_EXTRA_BYTES = 6
constexpr int32_t	REC_N_NEW_EXTRA_BYTES = 5
constexpr uint32_t	REC_N_TMP_EXTRA_BYTES = 1
constexpr auto	MAX_REC_PER_PAGE = UNIV_PAGE_SIZE_MAX / REC_N_NEW_EXTRA_BYTES
	Maximum number of records in a page. More...
constexpr uint32_t	REC_STATUS_ORDINARY = 0
constexpr uint32_t	REC_STATUS_NODE_PTR = 1
constexpr uint32_t	REC_STATUS_INFIMUM = 2
constexpr uint32_t	REC_STATUS_SUPREMUM = 3
constexpr uint32_t	REC_NODE_PTR_SIZE = 4
constexpr uint32_t	REC_1BYTE_SQL_NULL_MASK = 0x80UL
	SQL null flag in a 1-byte offset of ROW_FORMAT=REDUNDANT records. More...
constexpr uint32_t	REC_2BYTE_SQL_NULL_MASK = 0x8000UL
	SQL null flag in a 2-byte offset of ROW_FORMAT=REDUNDANT records. More...
constexpr uint32_t	REC_2BYTE_EXTERN_MASK = 0x4000UL
	In a 2-byte offset of ROW_FORMAT=REDUNDANT records, the second most significant bit denotes that the tail of a field is stored off-page. More...
constexpr uint32_t	REC_OFFS_HEADER_SIZE = 4
constexpr uint32_t	REC_OFFS_NORMAL_SIZE = 100
constexpr uint32_t	REC_OFFS_SMALL_SIZE = 10
static const uint8_t	REC_N_FIELDS_TWO_BYTES_FLAG = 0x80
	Number of fields flag which means it occupies two bytes. More...
static const uint8_t	REC_N_FIELDS_ONE_BYTE_MAX = 0x7F
	Max number of fields which can be stored in one byte. More...

Detailed Description

Record manager.

Created 5/30/1994 Heikki Tuuri

Enumeration Type Documentation

REC_INSERT_STATE

enum REC_INSERT_STATE

Enumerator
INSERTED_BEFORE_INSTANT_ADD_OLD_IMPLEMENTATION
INSERTED_AFTER_INSTANT_ADD_OLD_IMPLEMENTATION
INSERTED_AFTER_UPGRADE_BEFORE_INSTANT_ADD_NEW_IMPLEMENTATION
INSERTED_BEFORE_INSTANT_ADD_NEW_IMPLEMENTATION
INSERTED_AFTER_INSTANT_ADD_NEW_IMPLEMENTATION
INSERTED_INTO_TABLE_WITH_NO_INSTANT_NO_VERSION
NONE

Rec_instant_state

enum class Rec_instant_state

strong

Instant state of a record.

Determined by instant and version bit in info bits.

Enumerator
REC_IS_SIMPLE
REC_IS_VERSIONED
REC_IS_INSTANT

Function Documentation

get_rec_insert_state()

static enum REC_INSERT_STATE get_rec_insert_state ( const dict_index_t *  index, const rec_t *  rec, bool  temp  )

inlinestatic

init_nulls_lens_for_temp_redundant()

static enum REC_INSERT_STATE init_nulls_lens_for_temp_redundant ( const dict_index_t *  index, const rec_t *  rec, uint16_t *  n_null, const byte **  nulls, const byte **  lens, uint16_t &  non_default_fields, row_version_t &  row_version  )

inlinestatic

rec_get_1byte_offs_flag()

static bool rec_get_1byte_offs_flag ( const rec_t *  rec )

inlinestatic

The following function is used to test whether the data offsets in the record are stored in one-byte or two-byte format.

Returns

true if 1-byte form

Parameters

rec	in: physical record

rec_get_bit_field_1()

static ulint rec_get_bit_field_1 ( const rec_t *  rec, ulint  offs, ulint  mask, ulint  shift  )

inlinestatic

Gets a bit field from within 1 byte.

Parameters

rec	in: pointer to record origin
offs	in: offset from the origin down
mask	in: mask used to filter bits
shift	in: shift right applied after masking

rec_get_bit_field_2()

static uint16_t rec_get_bit_field_2 ( const rec_t *  rec, ulint  offs, ulint  mask, ulint  shift  )

inlinestatic

Gets a bit field from within 2 bytes.

Parameters

rec	in: pointer to record origin
offs	in: offset from the origin down
mask	in: mask used to filter bits
shift	in: shift right applied after masking

rec_get_info_bits()

static ulint rec_get_info_bits ( const rec_t *  rec, ulint  comp  )

inlinestatic

The following function is used to retrieve the info bits of a record.

Parameters

[in]	rec	physical record
[in]	comp	nonzero=compact page format

Returns

info bits

rec_get_info_bits_temp()

static ulint rec_get_info_bits_temp ( const rec_t *  rec )

inlinestatic

The following function is used to retrieve the info bits of a temporary record.

Parameters

[in]

rec

physical record

Returns

info bits

rec_get_instant_flag_new()

static bool rec_get_instant_flag_new ( const rec_t *  rec )

inlinestatic

The following function tells if a new-style record is instant record.

Parameters

[in]

rec

new-style record

Returns

true if it is instant affected

rec_get_instant_flag_new_temp()

static bool rec_get_instant_flag_new_temp ( const rec_t *  rec )

inlinestatic

The following function tells if a new-style temp record is instant record.

Parameters

[in]

rec

new-style temp record

Returns

true if it is instant affected

rec_get_instant_offset()

static uint64_t rec_get_instant_offset ( const dict_index_t *  index, ulint  n, uint64_t  offs  )

inlinestatic

Determine the offset of a specified field in the record, when this field is a field added after an instant ADD COLUMN.

Parameters

[in]	index	Clustered index where the record resides
[in]	n	Nth field to get offset
[in]	offs	Last offset before current field

Returns

The offset of the specified field

rec_get_n_fields()

static ulint rec_get_n_fields ( const rec_t *  rec, const dict_index_t *  index  )

inlinestatic

The following function is used to get the number of fields in a record.

If it's REDUNDANT record, the returned number would be a logic one which considers the fact that after instant ADD COLUMN, some records may have less fields than index.

Returns

number of data fields

Parameters

rec	in: physical record
index	in: record descriptor

rec_get_n_fields_instant()

static uint32_t rec_get_n_fields_instant ( const rec_t *  rec, const ulint  extra_bytes, uint16_t *  length  )

inlinestatic

Get the number of fields for one new style leaf page record.

This is only needed for table after instant ADD COLUMN.

Parameters

[in]	rec	leaf page record
[in]	extra_bytes	extra bytes of this record
[in,out]	length	length of number of fields

Returns

number of fields

rec_get_n_fields_old()

static uint16_t rec_get_n_fields_old ( const rec_t *  rec, const dict_index_t *  index  )

inlinestatic

The following function is used to get the number of fields in an old-style record.

Have to consider the case that after instant ADD COLUMN, this record may have less fields than current index.

Parameters

[in]	rec	physical record
[in]	index	index where the record resides

Returns

number of data fields

rec_get_n_fields_old_raw()

static uint16_t rec_get_n_fields_old_raw ( const rec_t *  rec )

inlinestatic

The following function is used to get the number of fields in an old-style record, which is stored in the rec.

Returns

number of data fields

Parameters

rec	in: physical record

rec_get_offsets()

ulint * rec_get_offsets	(	const rec_t *	rec,
		const dict_index_t *	index,
		ulint *	offsets,
		ulint	n_fields,
		ut::Location	location,
		mem_heap_t **	heap
	)

The following function determines the offsets to each field in the record.

It can reuse a previously allocated array. Note that after instant ADD COLUMN, if this is a record from clustered index, fields in the record may be less than the fields defined in the clustered index. So the offsets size is allocated according to the clustered index fields.

Parameters

[in]	rec	physical record
[in]	index	record descriptor
[in,out]	offsets	array consisting of offsets[0] allocated elements, or an array from rec_get_offsets(), or NULL
[in]	n_fields	maximum number of initialized fields (ULINT_UNDEFINED is all fields)
[in]	location	location where called
[in,out]	heap	memory heap

Returns

the new offsets

rec_get_offsets_reverse()

void rec_get_offsets_reverse	(	const byte *	extra,
		const dict_index_t *	index,
		ulint	node_ptr,
		ulint *	offsets
	)

The following function determines the offsets to each field in the record.

It can reuse a previously allocated array. in/out: array consisting of offsets[0] allocated elements

It can reuse a previously allocated array.

Parameters

extra	in: the extra bytes of a compact record in reverse order, excluding the fixed-size REC_N_NEW_EXTRA_BYTES
index	in: record descriptor
node_ptr	in: nonzero=node pointer, 0=leaf node
offsets	in/out: array consisting of offsets[0] allocated elements

rec_get_status()

static ulint rec_get_status ( const rec_t *  rec )

inlinestatic

The following function retrieves the status bits of a new-style record.

Returns

status bits

Parameters

rec	in: physical record

rec_info_bits_valid()

bool rec_info_bits_valid ( ulint  bits )

inline

Check if the info bits are valid.

Parameters

[in]

bits

info bits to check

Returns

true if valid

rec_init_fixed_offsets()

void rec_init_fixed_offsets ( const dict_index_t *  index, ulint *  offsets  )

inline

A simplified variant rec_init_offsets(rec, index, offsets) for the case in which the rec contains only fixed-length columns and non-NULL values in them, thus we can compute the offsets without looking at the rec.

Such offsets can be cached and reused for many recs which don't contain NULLs.

See also

rec_init_offsets for more details

Parameters

[in]	index	The index for which we want to cache the fixed offsets
[in,out]	offsets	The already allocated array to store the offsets. It should already have been initialized with rec_offs_set_n_alloc() and rec_offs_set_n_fields() before the call. This function will fill all the other elements.

rec_init_null_and_len_comp()

static enum REC_INSERT_STATE rec_init_null_and_len_comp ( const rec_t *  rec, const dict_index_t *  index, const byte **  nulls, const byte **  lens, uint16_t *  n_null, uint16_t &  non_default_fields, row_version_t &  row_version  )

inlinestatic

Determines the information about null bytes and variable length bytes for a new style record.

Parameters

[in]	rec	physical record
[in]	index	index where the record resides
[out]	nulls	the start of null bytes
[out]	lens	the start of variable length bytes
[out]	n_null	number of null fields
[out]	non_default_fields	non default fields from record
[out]	row_version	row version of the record

Returns

number of fields with no default or the row version of record

rec_init_null_and_len_temp()

static enum REC_INSERT_STATE rec_init_null_and_len_temp ( const rec_t *  rec, const dict_index_t *  index, const byte **  nulls, const byte **  lens, uint16_t *  n_null, uint16_t &  non_default_fields, row_version_t &  row_version  )

inlinestatic

Determines the information about null bytes and variable length bytes for a new-style temporary record.

Parameters

[in]	rec	physical record
[in]	index	index where the record resides
[out]	nulls	the start of null bytes
[out]	lens	the start of variable length bytes
[out]	n_null	number of null fields
[out]	non_default_fields	non default fields from record
[out]	row_version	row version of the record

Returns

the row inserted state

rec_init_offsets()

void rec_init_offsets	(	const rec_t *	rec,
		const dict_index_t *	index,
		ulint *	offsets
	)

The following function determines the offsets to each field in the record.

The offsets are written to a previously allocated array of ulint, where rec_offs_n_fields(offsets) has been initialized to the number of fields in the record. The rest of the array will be initialized by this function.

• rec_offs_base(offsets)[0] will be set to the extra size (if REC_OFFS_COMPACT is set, the record is in the new format; if REC_OFFS_EXTERNAL is set, the record contains externally stored columns).
• rec_offs_base(offsets)[1..n_fields] will be set to offsets past the end of fields 0..n_fields, or to the beginning of fields 1..n_fields+1.
• If the high-order bit of the offset at [i+1] is set (REC_OFFS_SQL_NULL), the field i is NULL.
• If the second high-order bit of the offset at [i+1] is set (REC_OFFS_EXTERNAL), the field i is being stored externally.

  Parameters

  [in]	rec	physical record
  [in]	index	record descriptor
  [in,out]	offsets	array of offsets

rec_init_offsets_comp_ordinary()

void rec_init_offsets_comp_ordinary ( const rec_t *  rec, bool  temp, const dict_index_t *  index, ulint *  offsets  )

inline

Determine the offset to each field in a leaf-page record in ROW_FORMAT=COMPACT.

This is a special case of rec_init_offsets() and rec_get_offsets().

Parameters

[in]	rec	physical record in ROW_FORMAT=COMPACT
[in]	temp	whether to use the format for temporary files in index creation
[in]	index	record descriptor
[in,out]	offsets	array of offsets

Note

This long method is made inline because it is on performance sensitive hot path. One must run performance tests if they intend to improve this method.

rec_n_fields_is_sane()

static bool rec_n_fields_is_sane ( dict_index_t *  index, const rec_t *  rec, const dtuple_t *  entry  )

inlinestatic

Confirms the n_fields of the entry is sane with comparing the other record in the same page specified.

Parameters

[in]	index	index
[in]	rec	record of the same page
[in]	entry	index entry

Returns

true if n_fields is sane

rec_new_is_versioned()

static bool rec_new_is_versioned ( const rec_t *  rec )

inlinestatic

The following function tells if a new-style record is versioned.

Parameters

[in]

rec

new-style (COMPACT/DYNAMIC) record

Returns

true if it is versioned

rec_new_temp_is_versioned()

static bool rec_new_temp_is_versioned ( const rec_t *  rec )

inlinestatic

The following function tells if a temporary record is versioned.

Parameters

[in]

rec

new-style temporary record

Returns

true if it's instant affected

rec_offs_base() [1/2]

static const ulint * rec_offs_base ( const ulint *  offsets )

inlinestatic

rec_offs_base() [2/2]

static ulint * rec_offs_base ( ulint *  offsets )

inlinestatic

rec_offs_cmp()

bool rec_offs_cmp	(	ulint *	offsets1,
		ulint *	offsets2
	)

Check if the given two record offsets are identical.

Parameters

[in]	offsets1	field offsets of a record
[in]	offsets2	field offsets of a record

Returns

true if they are identical, false otherwise.

rec_offs_get_n_alloc()

static ulint rec_offs_get_n_alloc ( const ulint *  offsets )

inlinestatic

The following function returns the number of allocated elements for an array of offsets.

Returns

number of elements

Parameters

offsets

in: array for rec_get_offsets()

rec_offs_make_valid()

static void rec_offs_make_valid ( const rec_t *  rec, const dict_index_t *  index, ulint *  offsets  )

inlinestatic

Updates debug data in offsets, in order to avoid bogus rec_offs_validate() failures.

Parameters

rec	in: record
index	in: record descriptor
offsets	in: array returned by rec_get_offsets()

rec_offs_n_fields()

static ulint rec_offs_n_fields ( const ulint *  offsets )

inlinestatic

The following function returns the number of fields in a record.

Returns

number of fields

Parameters

offsets

in: array returned by rec_get_offsets()

rec_offs_print()

std::ostream & rec_offs_print	(	std::ostream &	out,
		const ulint *	offsets
	)

Print the record offsets.

Parameters

[in]	out	the output stream to which offsets are printed.
[in]	offsets	the field offsets of the record.

Returns

the output stream.

rec_offs_set_n_alloc()

static void rec_offs_set_n_alloc ( ulint *  offsets, ulint  n_alloc  )

inlinestatic

The following function sets the number of allocated elements for an array of offsets.

Parameters

offsets	out: array for rec_get_offsets(), must be allocated
n_alloc	in: number of elements

rec_offs_set_n_fields()

static void rec_offs_set_n_fields ( ulint *  offsets, ulint  n_fields  )

inlinestatic

The following function sets the number of fields in offsets.

Parameters

offsets	in/out: array returned by rec_get_offsets()
n_fields	in: number of fields

rec_offs_validate()

static bool rec_offs_validate ( const rec_t *  rec, const dict_index_t *  index, const ulint *  offsets, const bool  check_status = true  )

inlinestatic

Validates offsets returned by rec_get_offsets().

Parameters

[in]	rec	record whose offsets are being validated or nullptr.
[in]	index	index to which record belongs or nullptr.
[in]	offsets	the record offsets array returned by rec_get_offsets()
[in]	check_status	if true, check status bits of the record.

Returns

true if valid

rec_old_is_versioned()

static bool rec_old_is_versioned ( const rec_t *  rec )

inlinestatic

The following function tells if an old-style record is versioned.

Parameters

[in]

rec

old-style (REDUNDANT) record

Returns

true if it's versioned

Variable Documentation

MAX_REC_PER_PAGE

constexpr auto MAX_REC_PER_PAGE = UNIV_PAGE_SIZE_MAX / REC_N_NEW_EXTRA_BYTES

constexpr

Maximum number of records in a page.

REC_1BYTE_SQL_NULL_MASK

constexpr uint32_t REC_1BYTE_SQL_NULL_MASK = 0x80UL

constexpr

SQL null flag in a 1-byte offset of ROW_FORMAT=REDUNDANT records.

REC_2BYTE_EXTERN_MASK

constexpr uint32_t REC_2BYTE_EXTERN_MASK = 0x4000UL

constexpr

In a 2-byte offset of ROW_FORMAT=REDUNDANT records, the second most significant bit denotes that the tail of a field is stored off-page.

REC_2BYTE_SQL_NULL_MASK

constexpr uint32_t REC_2BYTE_SQL_NULL_MASK = 0x8000UL

constexpr

SQL null flag in a 2-byte offset of ROW_FORMAT=REDUNDANT records.

REC_HEAP_NO_MASK

constexpr uint32_t REC_HEAP_NO_MASK = 0xFFF8UL

constexpr

REC_HEAP_NO_SHIFT

constexpr uint32_t REC_HEAP_NO_SHIFT = 3

constexpr

REC_INFO_BITS_MASK

constexpr uint32_t REC_INFO_BITS_MASK = 0xF0UL

constexpr

REC_INFO_BITS_SHIFT

constexpr uint32_t REC_INFO_BITS_SHIFT = 0

constexpr

REC_INFO_DELETED_FLAG

constexpr uint32_t REC_INFO_DELETED_FLAG = 0x20UL

constexpr

The deleted flag in info bits; when bit is set to 1, it means the record has been delete marked.

REC_INFO_INSTANT_FLAG

constexpr uint32_t REC_INFO_INSTANT_FLAG = 0x80UL

constexpr

The instant ADD COLUMN flag.

When it is set to 1, it means this record was inserted/updated after an instant ADD COLUMN.

REC_INFO_MIN_REC_FLAG

constexpr uint32_t REC_INFO_MIN_REC_FLAG = 0x10UL

constexpr

REC_INFO_VERSION_FLAG

constexpr uint32_t REC_INFO_VERSION_FLAG = 0x40UL

constexpr

REC_N_FIELDS_ONE_BYTE_MAX

const uint8_t REC_N_FIELDS_ONE_BYTE_MAX = 0x7F

static

Max number of fields which can be stored in one byte.

REC_N_FIELDS_TWO_BYTES_FLAG

const uint8_t REC_N_FIELDS_TWO_BYTES_FLAG = 0x80

static

Number of fields flag which means it occupies two bytes.

REC_N_NEW_EXTRA_BYTES

constexpr int32_t REC_N_NEW_EXTRA_BYTES = 5

constexpr

REC_N_OLD_EXTRA_BYTES

constexpr uint32_t REC_N_OLD_EXTRA_BYTES = 6

constexpr

REC_N_OWNED_MASK

constexpr uint32_t REC_N_OWNED_MASK = 0xFUL

constexpr

REC_N_OWNED_SHIFT

constexpr uint32_t REC_N_OWNED_SHIFT = 0

constexpr

REC_N_TMP_EXTRA_BYTES

constexpr uint32_t REC_N_TMP_EXTRA_BYTES = 1

constexpr

REC_NEW_HEAP_NO

constexpr uint32_t REC_NEW_HEAP_NO = 4

constexpr

REC_NEW_INFO_BITS

constexpr uint32_t REC_NEW_INFO_BITS = 5

constexpr

REC_NEW_N_OWNED

constexpr uint32_t REC_NEW_N_OWNED = 5

constexpr

REC_NEW_STATUS

constexpr uint32_t REC_NEW_STATUS = 3

constexpr

REC_NEW_STATUS_MASK

constexpr uint32_t REC_NEW_STATUS_MASK = 0x7UL

constexpr

REC_NEW_STATUS_SHIFT

constexpr uint32_t REC_NEW_STATUS_SHIFT = 0

constexpr

REC_NEXT

constexpr uint32_t REC_NEXT = 2

constexpr

REC_NEXT_MASK

constexpr uint32_t REC_NEXT_MASK = 0xFFFFUL

constexpr

REC_NEXT_SHIFT

constexpr uint32_t REC_NEXT_SHIFT = 0

constexpr

REC_NODE_PTR_SIZE

constexpr uint32_t REC_NODE_PTR_SIZE = 4

constexpr

REC_OFFS_COMPACT

constexpr uint32_t REC_OFFS_COMPACT = 1U << 31

constexpr

NOTE: The functions in this file should only use functions from other files in library.

The code in this file is used to make a library for external tools. Extra Bytes in Redudant Row Format

The extra bytes of the redundant row format (old row format) is explained here. It contains a total of 6 bytes that occurs before the record origin. These bits and bytes are accessed with reference to the record origin. So when we say 3rd byte, it means that it is 3rd byte from the record origin.

byte 6 byte 5 byte 4 byte 3 byte 2 byte 1 [iiiioooo][hhhhhhhh][hhhhhfff][fffffffs][pppppppp][pppppppp]+

1. The + is the record origin.
2. The next record pointer is given by the bits marked as 'p'. This takes 2 bytes - 1st and 2nd byte.
3. One bit is used to indicate whether the field offsets array uses 1 byte or 2 bytes each. This is given by the bit 's' in 3rd byte.
4. The total number of fields is given by the bits marked as 'f'. It spans the 4th and 3rd bytes. It uses a total of 10 bits.
5. The heap number of the record is given by the bits marked as 'h'. It spans the 5th and 4th bytes. It uses a total of 13 bits.
6. The record owned (by dir slot) information is given by bits marked as 'o'. It uses a total of 4 bits. It is available in the 6th byte.
7. The info bits are given by the bits marked as 'i'. It uses a total of 4 bits. It is available in the 6th byte.

REC_OFFS_DEFAULT

constexpr uint32_t REC_OFFS_DEFAULT = 1 << 29

constexpr

REC_OFFS_DROP

constexpr uint32_t REC_OFFS_DROP = 1 << 28

constexpr

REC_OFFS_EXTERNAL

constexpr uint32_t REC_OFFS_EXTERNAL = 1 << 30

constexpr

REC_OFFS_HEADER_SIZE

constexpr uint32_t REC_OFFS_HEADER_SIZE = 4

constexpr

REC_OFFS_MASK

constexpr uint32_t REC_OFFS_MASK = REC_OFFS_DROP - 1

constexpr

REC_OFFS_NORMAL_SIZE

constexpr uint32_t REC_OFFS_NORMAL_SIZE = 100

constexpr

REC_OFFS_SMALL_SIZE

constexpr uint32_t REC_OFFS_SMALL_SIZE = 10

constexpr

REC_OFFS_SQL_NULL

constexpr uint32_t REC_OFFS_SQL_NULL = 1U << 31

constexpr

REC_OLD_HEAP_NO

constexpr uint32_t REC_OLD_HEAP_NO = 5

constexpr

REC_OLD_INFO_BITS

constexpr uint32_t REC_OLD_INFO_BITS = 6

constexpr

REC_OLD_N_FIELDS

constexpr uint32_t REC_OLD_N_FIELDS = 4

constexpr

REC_OLD_N_FIELDS_MASK

constexpr uint32_t REC_OLD_N_FIELDS_MASK = 0x7FEUL

constexpr

REC_OLD_N_FIELDS_SHIFT

constexpr uint32_t REC_OLD_N_FIELDS_SHIFT = 1

constexpr

REC_OLD_N_OWNED

constexpr uint32_t REC_OLD_N_OWNED = 6

constexpr

REC_OLD_SHORT

constexpr uint32_t REC_OLD_SHORT = 3

constexpr

REC_OLD_SHORT_MASK

constexpr uint32_t REC_OLD_SHORT_MASK = 0x1UL

constexpr

REC_OLD_SHORT_SHIFT

constexpr uint32_t REC_OLD_SHORT_SHIFT = 0

constexpr

REC_STATUS_INFIMUM

constexpr uint32_t REC_STATUS_INFIMUM = 2

constexpr

REC_STATUS_NODE_PTR

constexpr uint32_t REC_STATUS_NODE_PTR = 1

constexpr

REC_STATUS_ORDINARY

constexpr uint32_t REC_STATUS_ORDINARY = 0

constexpr

REC_STATUS_SUPREMUM

constexpr uint32_t REC_STATUS_SUPREMUM = 3

constexpr

REC_TMP_INFO_BITS

constexpr uint32_t REC_TMP_INFO_BITS = 1

constexpr