Record manager. More...

#include "rem0rec.h"

Functions
static void	rec_set_nth_field_sql_null_low (rec_t *rec, ulint n)
	Set nth field value to SQL NULL. More...

static ulint	rec_offs_nth_sql_null_low (const ulint *offsets, ulint n)
	Returns nonzero if the SQL NULL bit is set in nth field of rec. More...

static ulint	rec_get_field_start_offs_low (const rec_t *rec, ulint n)
	Read the offset of the start of a data field in the record. More...

static ulint	rec_1_get_field_start_offs_low (const rec_t *rec, ulint n)
	Returns the offset of nth field start if the record is stored in the 1-byte offsets form. More...

static ulint	rec_1_get_field_end_info_low (const rec_t *rec, ulint n)
	Returns the offset of nth field end if the record is stored in the 1-byte offsets form. More...

static void	rec_1_set_field_end_info_low (rec_t *rec, ulint n, ulint info)
	Sets the field end info for the nth field if the record is stored in the 1-byte format. More...

static ulint	rec_2_get_field_start_offs_low (const rec_t *rec, ulint n)
	Returns the offset of nth field start if the record is stored in the 2-byte offsets form. More...

static ulint	rec_2_get_field_end_info_low (const rec_t *rec, ulint n)
	Returns the offset of nth field end if the record is stored in the 2-byte offsets form. More...

static void	rec_2_set_field_end_info_low (rec_t *rec, ulint n, ulint info)
	Sets the field end info for the nth field if the record is stored in the 2-byte format. More...

static void	rec_set_nth_field_null_bit_low (rec_t *rec, ulint i, bool val)
	Sets the value of the ith field SQL null bit of an old-style record. More...

static ulint	rec_get_nth_field_size_low (const rec_t *rec, ulint n)
	Gets the physical size of an old-style field. More...

static ulint	rec_get_nth_field_offs_old_low (const rec_t rec, ulint n, ulint len)
	The following function is used to get the offset to the nth data field in an old-style record. More...

static void	rec_offs_make_nth_extern_low (ulint *offsets, const ulint n)
	Mark the nth field as externally stored. More...

static ulint	rec_offs_nth_default_low (const ulint *offsets, ulint n)
	Returns nonzero if the default bit is set in nth field of rec. More...

static ulint	rec_offs_nth_size_low (const ulint *offsets, ulint n)
	Gets the physical size of a field. More...

static void	rec_set_nth_field_low (rec_t rec, const ulint offsets, ulint n, const void *data, ulint len)
	This is used to modify the value of an already existing field in a record. More...

Detailed Description

Record manager.

This file contains low level functions which deals with physical index of fields in a physical record.

After INSTANT ADD/DROP feature, fields index on logical record might not be same as field index on physical record. So a wrapper (rem0wrec.h) is implemented which translates logical index to physical index. And then functions of this file are called with physical index of the field.

Created 13/08/2021 Mayank Prasad

Function Documentation

◆ rec_1_get_field_end_info_low()

static ulint rec_1_get_field_end_info_low	(	const rec_t *	rec,
		ulint	n
	)

inlinestatic

Returns the offset of nth field end if the record is stored in the 1-byte offsets form.

If the field is SQL null, the flag is ORed in the returned value.

Parameters

[in]	rec	record
[in]	n	index of the field

Returns: offset of the start of the field, SQL null flag ORed

◆ rec_1_get_field_start_offs_low()

static ulint rec_1_get_field_start_offs_low	(	const rec_t *	rec,
		ulint	n
	)

inlinestatic

Returns the offset of nth field start if the record is stored in the 1-byte offsets form.

Parameters

[in]	rec	record
[in]	n	index of the field

Returns: offset of the start of the field

◆ rec_1_set_field_end_info_low()

static void rec_1_set_field_end_info_low	(	rec_t *	rec,
		ulint	n,
		ulint	info
	)

inlinestatic

Sets the field end info for the nth field if the record is stored in the 1-byte format.

Parameters

[in,out]	rec	record
[in]	n	index of the field
[in]	info	value to set

◆ rec_2_get_field_end_info_low()

static ulint rec_2_get_field_end_info_low	(	const rec_t *	rec,
		ulint	n
	)

inlinestatic

Returns the offset of nth field end if the record is stored in the 2-byte offsets form.

If the field is SQL null, the flag is ORed in the returned value.

Parameters

[in]	rec	record
[in]	n	index of the field

Returns: offset of the start of the field, SQL null flag and extern storage flag ORed

◆ rec_2_get_field_start_offs_low()

static ulint rec_2_get_field_start_offs_low	(	const rec_t *	rec,
		ulint	n
	)

inlinestatic

Returns the offset of nth field start if the record is stored in the 2-byte offsets form.

Parameters

[in]	rec	record
[in]	n	index of the field

Returns: offset of the start of the field

◆ rec_2_set_field_end_info_low()

static void rec_2_set_field_end_info_low	(	rec_t *	rec,
		ulint	n,
		ulint	info
	)

inlinestatic

Sets the field end info for the nth field if the record is stored in the 2-byte format.

Parameters

[in]	rec	record
[in]	n	index of the field
[out]	info	end info

◆ rec_get_field_start_offs_low()

static ulint rec_get_field_start_offs_low	(	const rec_t *	rec,
		ulint	n
	)

inlinestatic

Read the offset of the start of a data field in the record.

The start of an SQL null field is the end offset of the previous non-null field, or 0, if none exists. If n is the number of the last field + 1, then the end offset of the last field is returned.

Parameters

[in]	rec	record
[in]	n	index of the field

Returns: offset of the start of the field

◆ rec_get_nth_field_offs_old_low()

static ulint rec_get_nth_field_offs_old_low	(	const rec_t *	rec,
		ulint	n,
		ulint *	len
	)

inlinestatic

The following function is used to get the offset to the nth data field in an old-style record.

Parameters

[in]	rec	record
[in]	n	index of the field
[out]	len	length of the field; UNIV_SQL_NULL if SQL null;

Returns: offset to the field

◆ rec_get_nth_field_size_low()

static ulint rec_get_nth_field_size_low	(	const rec_t *	rec,
		ulint	n
	)

inlinestatic

Gets the physical size of an old-style field.

Also an SQL null may have a field of size > 0, if the data type is of a fixed size.

Parameters

[in]	rec	record
[in]	n	index of the field

Returns: field size in bytes

◆ rec_offs_make_nth_extern_low()

static void rec_offs_make_nth_extern_low	(	ulint *	offsets,
		const ulint	n
	)

inlinestatic

Mark the nth field as externally stored.

Parameters

[in]	offsets	array returned by rec_get_offsets()
[in]	n	index of the field

◆ rec_offs_nth_default_low()

static ulint rec_offs_nth_default_low	(	const ulint *	offsets,
		ulint	n
	)

inlinestatic

Returns nonzero if the default bit is set in nth field of rec.

Parameters

[in]	offsets	array returned by rec_get_offsets()
[in]	n	index of the field

Returns: nonzero if default bit is set

◆ rec_offs_nth_size_low()

static ulint rec_offs_nth_size_low	(	const ulint *	offsets,
		ulint	n
	)

inlinestatic

Gets the physical size of a field.

Parameters

[in]	offsets	array returned by rec_get_offsets()
[in]	n	index of the field

Returns: length of field

◆ rec_offs_nth_sql_null_low()

static ulint rec_offs_nth_sql_null_low	(	const ulint *	offsets,
		ulint	n
	)

inlinestatic

Returns nonzero if the SQL NULL bit is set in nth field of rec.

Parameters

[in]	offsets	array returned by rec_get_offsets()
[in]	n	index of the field.

Returns: nonzero if SQL NULL

◆ rec_set_nth_field_low()

static void rec_set_nth_field_low	(	rec_t *	rec,
		const ulint *	offsets,
		ulint	n,
		const void *	data,
		ulint	len
	)

inlinestatic

This is used to modify the value of an already existing field in a record.

The previous value must have exactly the same size as the new value. If len is UNIV_SQL_NULL then the field is treated as an SQL null. For records in ROW_FORMAT=COMPACT (new-style records), len must not be UNIV_SQL_NULL unless the field already is SQL null.

Parameters

[in]	rec	record
[in]	offsets	array returned by rec_get_offsets()
[in]	n	index of the field
[in]	data	pointer to the data if not SQL null
[in]	len	length of the data or UNIV_SQL_NULL

◆ rec_set_nth_field_null_bit_low()

static void rec_set_nth_field_null_bit_low	(	rec_t *	rec,
		ulint	i,
		bool	val
	)

inlinestatic

Sets the value of the ith field SQL null bit of an old-style record.

Parameters

[in]	rec	record
[in]	i	index of the field
[in]	val	value to set

◆ rec_set_nth_field_sql_null_low()

static void rec_set_nth_field_sql_null_low	(	rec_t *	rec,
		ulint	n
	)

inlinestatic

Set nth field value to SQL NULL.

Parameters

[in,out]	rec	record
[in]	n	index of the field.

Functions

Detailed Description

Function Documentation

◆ rec_1_get_field_end_info_low()

◆ rec_1_get_field_start_offs_low()

◆ rec_1_set_field_end_info_low()

◆ rec_2_get_field_end_info_low()

◆ rec_2_get_field_start_offs_low()

◆ rec_2_set_field_end_info_low()

◆ rec_get_field_start_offs_low()

◆ rec_get_nth_field_offs_old_low()

◆ rec_get_nth_field_size_low()

◆ rec_offs_make_nth_extern_low()

◆ rec_offs_nth_default_low()

◆ rec_offs_nth_size_low()

◆ rec_offs_nth_sql_null_low()

◆ rec_set_nth_field_low()

◆ rec_set_nth_field_null_bit_low()

◆ rec_set_nth_field_sql_null_low()