path: root/storage/innobase/include/row0row.h

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/**************************************************//**
@file include/row0row.h
General row routines

Created 4/20/1996 Heikki Tuuri
*******************************************************/

#ifndef row0row_h
#define row0row_h

#include "univ.i"
#include "data0data.h"
#include "dict0types.h"
#include "trx0types.h"
#include "que0types.h"
#include "mtr0mtr.h"
#include "rem0types.h"
#include "read0types.h"
#include "row0types.h"
#include "btr0types.h"

/*********************************************************************//**
Gets the offset of the DB_TRX_ID field, in bytes relative to the origin of
a clustered index record.
@return	offset of DATA_TRX_ID */
UNIV_INLINE
ulint
row_get_trx_id_offset(
/*==================*/
	const dict_index_t*	index,	/*!< in: clustered index */
	const ulint*		offsets)/*!< in: record offsets */
	__attribute__((nonnull, warn_unused_result));
/*********************************************************************//**
Reads the trx id field from a clustered index record.
@return	value of the field */
UNIV_INLINE
trx_id_t
row_get_rec_trx_id(
/*===============*/
	const rec_t*		rec,	/*!< in: record */
	const dict_index_t*	index,	/*!< in: clustered index */
	const ulint*		offsets)/*!< in: rec_get_offsets(rec, index) */
	__attribute__((nonnull, warn_unused_result));
/*********************************************************************//**
Reads the roll pointer field from a clustered index record.
@return	value of the field */
UNIV_INLINE
roll_ptr_t
row_get_rec_roll_ptr(
/*=================*/
	const rec_t*		rec,	/*!< in: record */
	const dict_index_t*	index,	/*!< in: clustered index */
	const ulint*		offsets)/*!< in: rec_get_offsets(rec, index) */
	__attribute__((nonnull, warn_unused_result));
/*****************************************************************//**
When an insert or purge to a table is performed, this function builds
the entry to be inserted into or purged from an index on the table.
@return index entry which should be inserted or purged
@retval NULL if the externally stored columns in the clustered index record
are unavailable and ext != NULL, or row is missing some needed columns. */
UNIV_INTERN
dtuple_t*
row_build_index_entry_low(
/*======================*/
	const dtuple_t*		row,	/*!< in: row which should be
					inserted or purged */
	const row_ext_t*	ext,	/*!< in: externally stored column
					prefixes, or NULL */
	dict_index_t*		index,	/*!< in: index on the table */
	mem_heap_t*		heap)	/*!< in: memory heap from which
					the memory for the index entry
					is allocated */
	__attribute__((warn_unused_result, nonnull(1,3,4)));
/*****************************************************************//**
When an insert or purge to a table is performed, this function builds
the entry to be inserted into or purged from an index on the table.
@return index entry which should be inserted or purged, or NULL if the
externally stored columns in the clustered index record are
unavailable and ext != NULL */
UNIV_INLINE
dtuple_t*
row_build_index_entry(
/*==================*/
	const dtuple_t*		row,	/*!< in: row which should be
					inserted or purged */
	const row_ext_t*	ext,	/*!< in: externally stored column
					prefixes, or NULL */
	dict_index_t*		index,	/*!< in: index on the table */
	mem_heap_t*		heap)	/*!< in: memory heap from which
					the memory for the index entry
					is allocated */
	__attribute__((warn_unused_result, nonnull(1,3,4)));
/*******************************************************************//**
An inverse function to row_build_index_entry. Builds a row from a
record in a clustered index.
@return	own: row built; see the NOTE below! */
UNIV_INTERN
dtuple_t*
row_build(
/*======*/
	ulint			type,	/*!< in: ROW_COPY_POINTERS or
					ROW_COPY_DATA; the latter
					copies also the data fields to
					heap while the first only
					places pointers to data fields
					on the index page, and thus is
					more efficient */
	const dict_index_t*	index,	/*!< in: clustered index */
	const rec_t*		rec,	/*!< in: record in the clustered
					index; NOTE: in the case
					ROW_COPY_POINTERS the data
					fields in the row will point
					directly into this record,
					therefore, the buffer page of
					this record must be at least
					s-latched and the latch held
					as long as the row dtuple is used! */
	const ulint*		offsets,/*!< in: rec_get_offsets(rec,index)
					or NULL, in which case this function
					will invoke rec_get_offsets() */
	const dict_table_t*	col_table,
					/*!< in: table, to check which
					externally stored columns
					occur in the ordering columns
					of an index, or NULL if
					index->table should be
					consulted instead; the user
					columns in this table should be
					the same columns as in index->table */
	const dtuple_t*		add_cols,
					/*!< in: default values of
					added columns, or NULL */
	const ulint*		col_map,/*!< in: mapping of old column
					numbers to new ones, or NULL */
	row_ext_t**		ext,	/*!< out, own: cache of
					externally stored column
					prefixes, or NULL */
	mem_heap_t*		heap)	/*!< in: memory heap from which
					the memory needed is allocated */
	__attribute__((nonnull(2,3,9)));
/*******************************************************************//**
Converts an index record to a typed data tuple.
@return index entry built; does not set info_bits, and the data fields
in the entry will point directly to rec */
UNIV_INTERN
dtuple_t*
row_rec_to_index_entry_low(
/*=======================*/
	const rec_t*		rec,	/*!< in: record in the index */
	const dict_index_t*	index,	/*!< in: index */
	const ulint*		offsets,/*!< in: rec_get_offsets(rec, index) */
	ulint*			n_ext,	/*!< out: number of externally
					stored columns */
	mem_heap_t*		heap)	/*!< in: memory heap from which
					the memory needed is allocated */
	__attribute__((nonnull, warn_unused_result));
/*******************************************************************//**
Converts an index record to a typed data tuple. NOTE that externally
stored (often big) fields are NOT copied to heap.
@return	own: index entry built */
UNIV_INTERN
dtuple_t*
row_rec_to_index_entry(
/*===================*/
	const rec_t*		rec,	/*!< in: record in the index */
	const dict_index_t*	index,	/*!< in: index */
	const ulint*		offsets,/*!< in/out: rec_get_offsets(rec) */
	ulint*			n_ext,	/*!< out: number of externally
					stored columns */
	mem_heap_t*		heap)	/*!< in: memory heap from which
					the memory needed is allocated */
	__attribute__((nonnull, warn_unused_result));
/*******************************************************************//**
Builds from a secondary index record a row reference with which we can
search the clustered index record.
@return	own: row reference built; see the NOTE below! */
UNIV_INTERN
dtuple_t*
row_build_row_ref(
/*==============*/
	ulint		type,	/*!< in: ROW_COPY_DATA, or ROW_COPY_POINTERS:
				the former copies also the data fields to
				heap, whereas the latter only places pointers
				to data fields on the index page */
	dict_index_t*	index,	/*!< in: secondary index */
	const rec_t*	rec,	/*!< in: record in the index;
				NOTE: in the case ROW_COPY_POINTERS
				the data fields in the row will point
				directly into this record, therefore,
				the buffer page of this record must be
				at least s-latched and the latch held
				as long as the row reference is used! */
	mem_heap_t*	heap)	/*!< in: memory heap from which the memory
				needed is allocated */
	__attribute__((nonnull, warn_unused_result));
/*******************************************************************//**
Builds from a secondary index record a row reference with which we can
search the clustered index record. */
UNIV_INTERN
void
row_build_row_ref_in_tuple(
/*=======================*/
	dtuple_t*		ref,	/*!< in/out: row reference built;
					see the NOTE below! */
	const rec_t*		rec,	/*!< in: record in the index;
					NOTE: the data fields in ref
					will point directly into this
					record, therefore, the buffer
					page of this record must be at
					least s-latched and the latch
					held as long as the row
					reference is used! */
	const dict_index_t*	index,	/*!< in: secondary index */
	ulint*			offsets,/*!< in: rec_get_offsets(rec, index)
					or NULL */
	trx_t*			trx)	/*!< in: transaction or NULL */
	__attribute__((nonnull(1,2,3)));
/*******************************************************************//**
Builds from a secondary index record a row reference with which we can
search the clustered index record. */
UNIV_INLINE
void
row_build_row_ref_fast(
/*===================*/
	dtuple_t*	ref,	/*!< in/out: typed data tuple where the
				reference is built */
	const ulint*	map,	/*!< in: array of field numbers in rec
				telling how ref should be built from
				the fields of rec */
	const rec_t*	rec,	/*!< in: record in the index; must be
				preserved while ref is used, as we do
				not copy field values to heap */
	const ulint*	offsets);/*!< in: array returned by rec_get_offsets() */
/***************************************************************//**
Searches the clustered index record for a row, if we have the row
reference.
@return	TRUE if found */
UNIV_INTERN
ibool
row_search_on_row_ref(
/*==================*/
	btr_pcur_t*		pcur,	/*!< out: persistent cursor, which must
					be closed by the caller */
	ulint			mode,	/*!< in: BTR_MODIFY_LEAF, ... */
	const dict_table_t*	table,	/*!< in: table */
	const dtuple_t*		ref,	/*!< in: row reference */
	mtr_t*			mtr)	/*!< in/out: mtr */
	__attribute__((nonnull, warn_unused_result));
/*********************************************************************//**
Fetches the clustered index record for a secondary index record. The latches
on the secondary index record are preserved.
@return	record or NULL, if no record found */
UNIV_INTERN
rec_t*
row_get_clust_rec(
/*==============*/
	ulint		mode,	/*!< in: BTR_MODIFY_LEAF, ... */
	const rec_t*	rec,	/*!< in: record in a secondary index */
	dict_index_t*	index,	/*!< in: secondary index */
	dict_index_t**	clust_index,/*!< out: clustered index */
	mtr_t*		mtr)	/*!< in: mtr */
	__attribute__((nonnull, warn_unused_result));

/** Result of row_search_index_entry */
enum row_search_result {
	ROW_FOUND = 0,		/*!< the record was found */
	ROW_NOT_FOUND,		/*!< record not found */
	ROW_BUFFERED,		/*!< one of BTR_INSERT, BTR_DELETE, or
				BTR_DELETE_MARK was specified, the
				secondary index leaf page was not in
				the buffer pool, and the operation was
				enqueued in the insert/delete buffer */
	ROW_NOT_DELETED_REF	/*!< BTR_DELETE was specified, and
				row_purge_poss_sec() failed */
};

/***************************************************************//**
Searches an index record.
@return	whether the record was found or buffered */
UNIV_INTERN
enum row_search_result
row_search_index_entry(
/*===================*/
	dict_index_t*	index,	/*!< in: index */
	const dtuple_t*	entry,	/*!< in: index entry */
	ulint		mode,	/*!< in: BTR_MODIFY_LEAF, ... */
	btr_pcur_t*	pcur,	/*!< in/out: persistent cursor, which must
				be closed by the caller */
	mtr_t*		mtr)	/*!< in: mtr */
	__attribute__((nonnull, warn_unused_result));

#define ROW_COPY_DATA		1
#define ROW_COPY_POINTERS	2

/* The allowed latching order of index records is the following:
(1) a secondary index record ->
(2) the clustered index record ->
(3) rollback segment data for the clustered index record. */

/*******************************************************************//**
Formats the raw data in "data" (in InnoDB on-disk format) using
"dict_field" and writes the result to "buf".
Not more than "buf_size" bytes are written to "buf".
The result is always NUL-terminated (provided buf_size is positive) and the
number of bytes that were written to "buf" is returned (including the
terminating NUL).
@return	number of bytes that were written */
UNIV_INTERN
ulint
row_raw_format(
/*===========*/
	const char*		data,		/*!< in: raw data */
	ulint			data_len,	/*!< in: raw data length
						in bytes */
	const dict_field_t*	dict_field,	/*!< in: index field */
	char*			buf,		/*!< out: output buffer */
	ulint			buf_size)	/*!< in: output buffer size
						in bytes */
	__attribute__((nonnull, warn_unused_result));

#ifndef UNIV_NONINL
#include "row0row.ic"
#endif

#endif