mariadb/storage/innobase/row/row0row.c

/******************************************************
General row routines

(c) 1996 Innobase Oy

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

#include "row0row.h"

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

#include "dict0dict.h"
#include "btr0btr.h"
#include "mach0data.h"
#include "trx0rseg.h"
#include "trx0trx.h"
#include "trx0roll.h"
#include "trx0undo.h"
#include "trx0purge.h"
#include "trx0rec.h"
#include "que0que.h"
#include "row0row.h"
#include "row0upd.h"
#include "rem0cmp.h"
#include "read0read.h"

/*************************************************************************
Reads the trx id or roll ptr field from a clustered index record: this function
is slower than the specialized inline functions. */

dulint
row_get_rec_sys_field(
/*==================*/
				/* out: value of the field */
	ulint		type,	/* in: DATA_TRX_ID or DATA_ROLL_PTR */
	rec_t*		rec,	/* in: record */
	dict_index_t*	index,	/* in: clustered index */
	const ulint*	offsets)/* in: rec_get_offsets(rec, index) */
{
	ulint		pos;
	byte*		field;
	ulint		len;

	ut_ad(index->type & DICT_CLUSTERED);

	pos = dict_index_get_sys_col_pos(index, type);

	field = rec_get_nth_field(rec, offsets, pos, &len);

	if (type == DATA_TRX_ID) {

		return(trx_read_trx_id(field));
	} else {
		ut_ad(type == DATA_ROLL_PTR);

		return(trx_read_roll_ptr(field));
	}
}

/*************************************************************************
Sets the trx id or roll ptr field in a clustered index record: this function
is slower than the specialized inline functions. */

void
row_set_rec_sys_field(
/*==================*/
				/* out: value of the field */
	ulint		type,	/* in: DATA_TRX_ID or DATA_ROLL_PTR */
	rec_t*		rec,	/* in: record */
	dict_index_t*	index,	/* in: clustered index */
	const ulint*	offsets,/* in: rec_get_offsets(rec, index) */
	dulint		val)	/* in: value to set */
{
	ulint	pos;
	byte*	field;
	ulint	len;

	ut_ad(index->type & DICT_CLUSTERED);
	ut_ad(rec_offs_validate(rec, index, offsets));

	pos = dict_index_get_sys_col_pos(index, type);

	field = rec_get_nth_field(rec, offsets, pos, &len);

	if (type == DATA_TRX_ID) {

		trx_write_trx_id(field, val);
	} else {
		ut_ad(type == DATA_ROLL_PTR);

		trx_write_roll_ptr(field, val);
	}
}

/*********************************************************************
When an insert to a table is performed, this function builds the entry which
has to be inserted to an index on the table. */

dtuple_t*
row_build_index_entry(
/*==================*/
				/* out: index entry which should be inserted */
	dtuple_t*	row,	/* in: row which should be inserted to the
				table */
	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 */
{
	dtuple_t*	entry;
	ulint		entry_len;
	dict_field_t*	ind_field;
	dfield_t*	dfield;
	dfield_t*	dfield2;
	ulint		i;
	ulint		storage_len;

	ut_ad(row && index && heap);
	ut_ad(dtuple_check_typed(row));

	entry_len = dict_index_get_n_fields(index);
	entry = dtuple_create(heap, entry_len);

	if (index->type & DICT_UNIVERSAL) {
		dtuple_set_n_fields_cmp(entry, entry_len);
	} else {
		dtuple_set_n_fields_cmp(
			entry, dict_index_get_n_unique_in_tree(index));
	}

	for (i = 0; i < entry_len; i++) {
		const dict_col_t*	col;
		ind_field = dict_index_get_nth_field(index, i);
		col = ind_field->col;

		dfield = dtuple_get_nth_field(entry, i);

		dfield2 = dtuple_get_nth_field(row, dict_col_get_no(col));

		dfield_copy(dfield, dfield2);

		/* If a column prefix index, take only the prefix */
		if (ind_field->prefix_len > 0
		    && dfield_get_len(dfield2) != UNIV_SQL_NULL) {

			storage_len = dtype_get_at_most_n_mbchars(
				col->prtype, col->mbminlen, col->mbmaxlen,
				ind_field->prefix_len,
				dfield_get_len(dfield2), dfield2->data);

			dfield_set_len(dfield, storage_len);
		}
	}

	ut_ad(dtuple_check_typed(entry));

	return(entry);
}

/***********************************************************************
An inverse function to dict_row_build_index_entry. Builds a row from a
record in a clustered index. */

dtuple_t*
row_build(
/*======*/
				/* out, own: row built; see the NOTE below! */
	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 */
	dict_index_t*	index,	/* in: clustered index */
	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() */
	mem_heap_t*	heap)	/* in: memory heap from which the memory
				needed is allocated */
{
	dtuple_t*	row;
	dict_table_t*	table;
	dict_field_t*	ind_field;
	dfield_t*	dfield;
	ulint		n_fields;
	byte*		field;
	ulint		len;
	ulint		row_len;
	byte*		buf;
	ulint		i;
	mem_heap_t*	tmp_heap	= NULL;
	ulint		offsets_[REC_OFFS_NORMAL_SIZE];
	*offsets_ = (sizeof offsets_) / sizeof *offsets_;

	ut_ad(index && rec && heap);
	ut_ad(index->type & DICT_CLUSTERED);
	ut_ad(!mutex_own(&kernel_mutex));

	if (!offsets) {
		offsets = rec_get_offsets(rec, index, offsets_,
					  ULINT_UNDEFINED, &tmp_heap);
	} else {
		ut_ad(rec_offs_validate(rec, index, offsets));
	}

#if defined UNIV_DEBUG || defined UNIV_BLOB_LIGHT_DEBUG
	/* This condition can occur during crash recovery before
	trx_rollback_or_clean_all_without_sess() has completed
	execution.

	This condition is possible if the server crashed
	during an insert or update before
	btr_store_big_rec_extern_fields() did mtr_commit() all
	BLOB pointers to the clustered index record.

	If the record contains a null BLOB pointer, look up the
	transaction that holds the implicit lock on this record, and
	assert that it is active. (In this version of InnoDB, we
	cannot assert that it was recovered, because there is no
	trx->is_recovered field.) */

	ut_a(!rec_offs_any_null_extern(rec, offsets)
	     || trx_assert_active(row_get_rec_trx_id(rec, index, offsets)));
#endif /* UNIV_DEBUG || UNIV_BLOB_LIGHT_DEBUG */

	if (type != ROW_COPY_POINTERS) {
		/* Take a copy of rec to heap */
		buf = mem_heap_alloc(heap, rec_offs_size(offsets));
		rec = rec_copy(buf, rec, offsets);
		/* Avoid a debug assertion in rec_offs_validate(). */
		rec_offs_make_valid(rec, index, (ulint*) offsets);
	}

	table = index->table;
	row_len = dict_table_get_n_cols(table);

	row = dtuple_create(heap, row_len);

	dtuple_set_info_bits(row, rec_get_info_bits(
				     rec, dict_table_is_comp(table)));

	n_fields = rec_offs_n_fields(offsets);

	dict_table_copy_types(row, table);

	for (i = 0; i < n_fields; i++) {
		ind_field = dict_index_get_nth_field(index, i);

		if (ind_field->prefix_len == 0) {

			const dict_col_t*	col
				= dict_field_get_col(ind_field);

			dfield = dtuple_get_nth_field(row,
						      dict_col_get_no(col));
			field = rec_get_nth_field(rec, offsets, i, &len);

			dfield_set_data(dfield, field, len);
		}
	}

	ut_ad(dtuple_check_typed(row));

	if (tmp_heap) {
		mem_heap_free(tmp_heap);
	}

	return(row);
}

/***********************************************************************
Converts an index record to a typed data tuple. NOTE that externally
stored (often big) fields are NOT copied to heap. */

dtuple_t*
row_rec_to_index_entry(
/*===================*/
				/* out, own: index entry built; see the
				NOTE below! */
	ulint		type,	/* in: ROW_COPY_DATA, or ROW_COPY_POINTERS:
				the former copies also the data fields to
				heap as the latter only places pointers to
				data fields on the index page */
	dict_index_t*	index,	/* in: index */
	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 dtuple is used! */
	mem_heap_t*	heap)	/* in: memory heap from which the memory
				needed is allocated */
{
	dtuple_t*	entry;
	dfield_t*	dfield;
	ulint		i;
	byte*		field;
	ulint		len;
	ulint		rec_len;
	byte*		buf;
	mem_heap_t*	tmp_heap	= NULL;
	ulint		offsets_[REC_OFFS_NORMAL_SIZE];
	ulint*		offsets		= offsets_;
	*offsets_ = (sizeof offsets_) / sizeof *offsets_;

	ut_ad(rec && heap && index);

	offsets = rec_get_offsets(rec, index, offsets,
				  ULINT_UNDEFINED, &tmp_heap);

	if (type == ROW_COPY_DATA) {
		/* Take a copy of rec to heap */
		buf = mem_heap_alloc(heap, rec_offs_size(offsets));
		rec = rec_copy(buf, rec, offsets);
		/* Avoid a debug assertion in rec_offs_validate(). */
		rec_offs_make_valid(rec, index, offsets);
#if defined UNIV_DEBUG || defined UNIV_BLOB_LIGHT_DEBUG
	} else {
		ut_a(!rec_offs_any_null_extern(rec, offsets));
#endif /* UNIV_DEBUG || UNIV_BLOB_LIGHT_DEBUG */
	}

	rec_len = rec_offs_n_fields(offsets);

	entry = dtuple_create(heap, rec_len);

	dtuple_set_n_fields_cmp(entry,
				dict_index_get_n_unique_in_tree(index));
	ut_ad(rec_len == dict_index_get_n_fields(index));

	dict_index_copy_types(entry, index, rec_len);

	dtuple_set_info_bits(entry,
			     rec_get_info_bits(rec, rec_offs_comp(offsets)));

	for (i = 0; i < rec_len; i++) {

		dfield = dtuple_get_nth_field(entry, i);
		field = rec_get_nth_field(rec, offsets, i, &len);

		dfield_set_data(dfield, field, len);
	}

	ut_ad(dtuple_check_typed(entry));
	if (tmp_heap) {
		mem_heap_free(tmp_heap);
	}

	return(entry);
}

/***********************************************************************
Builds from a secondary index record a row reference with which we can
search the clustered index record. */

dtuple_t*
row_build_row_ref(
/*==============*/
				/* out, own: row reference built; see the
				NOTE below! */
	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: index */
	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 */
{
	dict_table_t*	table;
	dict_index_t*	clust_index;
	dfield_t*	dfield;
	dtuple_t*	ref;
	byte*		field;
	ulint		len;
	ulint		ref_len;
	ulint		pos;
	byte*		buf;
	ulint		clust_col_prefix_len;
	ulint		i;
	mem_heap_t*	tmp_heap	= NULL;
	ulint		offsets_[REC_OFFS_NORMAL_SIZE];
	ulint*		offsets		= offsets_;
	*offsets_ = (sizeof offsets_) / sizeof *offsets_;

	ut_ad(index && rec && heap);

	offsets = rec_get_offsets(rec, index, offsets,
				  ULINT_UNDEFINED, &tmp_heap);

	if (type == ROW_COPY_DATA) {
		/* Take a copy of rec to heap */

		buf = mem_heap_alloc(heap, rec_offs_size(offsets));

		rec = rec_copy(buf, rec, offsets);
		/* Avoid a debug assertion in rec_offs_validate(). */
		rec_offs_make_valid(rec, index, offsets);
	}

	table = index->table;

	clust_index = dict_table_get_first_index(table);

	ref_len = dict_index_get_n_unique(clust_index);

	ref = dtuple_create(heap, ref_len);

	dict_index_copy_types(ref, clust_index, ref_len);

	for (i = 0; i < ref_len; i++) {
		dfield = dtuple_get_nth_field(ref, i);

		pos = dict_index_get_nth_field_pos(index, clust_index, i);

		ut_a(pos != ULINT_UNDEFINED);

		field = rec_get_nth_field(rec, offsets, pos, &len);

		dfield_set_data(dfield, field, len);

		/* If the primary key contains a column prefix, then the
		secondary index may contain a longer prefix of the same
		column, or the full column, and we must adjust the length
		accordingly. */

		clust_col_prefix_len = dict_index_get_nth_field(
			clust_index, i)->prefix_len;

		if (clust_col_prefix_len > 0) {
			if (len != UNIV_SQL_NULL) {

				const dtype_t*	dtype
					= dfield_get_type(dfield);

				dfield_set_len(dfield,
					       dtype_get_at_most_n_mbchars(
						       dtype->prtype,
						       dtype->mbminlen,
						       dtype->mbmaxlen,
						       clust_col_prefix_len,
						       len, (char*) field));
			}
		}
	}

	ut_ad(dtuple_check_typed(ref));
	if (tmp_heap) {
		mem_heap_free(tmp_heap);
	}

	return(ref);
}

/***********************************************************************
Builds from a secondary index record a row reference with which we can
search the clustered index record. */

void
row_build_row_ref_in_tuple(
/*=======================*/
	dtuple_t*	ref,	/* in/out: row reference built; see the
				NOTE below! */
	dict_index_t*	index,	/* in: index */
	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! */
	trx_t*		trx)	/* in: transaction */
{
	dict_index_t*	clust_index;
	dfield_t*	dfield;
	byte*		field;
	ulint		len;
	ulint		ref_len;
	ulint		pos;
	ulint		clust_col_prefix_len;
	ulint		i;
	mem_heap_t*	heap		= NULL;
	ulint		offsets_[REC_OFFS_NORMAL_SIZE];
	ulint*		offsets		= offsets_;
	*offsets_ = (sizeof offsets_) / sizeof *offsets_;

	ut_a(ref);
	ut_a(index);
	ut_a(rec);

	if (UNIV_UNLIKELY(!index->table)) {
		fputs("InnoDB: table ", stderr);
notfound:
		ut_print_name(stderr, trx, TRUE, index->table_name);
		fputs(" for index ", stderr);
		ut_print_name(stderr, trx, FALSE, index->name);
		fputs(" not found\n", stderr);
		ut_error;
	}

	clust_index = dict_table_get_first_index(index->table);

	if (!clust_index) {
		fputs("InnoDB: clust index for table ", stderr);
		goto notfound;
	}

	offsets = rec_get_offsets(rec, index, offsets, ULINT_UNDEFINED, &heap);

	ref_len = dict_index_get_n_unique(clust_index);

	ut_ad(ref_len == dtuple_get_n_fields(ref));

	dict_index_copy_types(ref, clust_index, ref_len);

	for (i = 0; i < ref_len; i++) {
		dfield = dtuple_get_nth_field(ref, i);

		pos = dict_index_get_nth_field_pos(index, clust_index, i);

		ut_a(pos != ULINT_UNDEFINED);

		field = rec_get_nth_field(rec, offsets, pos, &len);

		dfield_set_data(dfield, field, len);

		/* If the primary key contains a column prefix, then the
		secondary index may contain a longer prefix of the same
		column, or the full column, and we must adjust the length
		accordingly. */

		clust_col_prefix_len = dict_index_get_nth_field(
			clust_index, i)->prefix_len;

		if (clust_col_prefix_len > 0) {
			if (len != UNIV_SQL_NULL) {

				const dtype_t*	dtype
					= dfield_get_type(dfield);

				dfield_set_len(dfield,
					       dtype_get_at_most_n_mbchars(
						       dtype->prtype,
						       dtype->mbminlen,
						       dtype->mbmaxlen,
						       clust_col_prefix_len,
						       len, (char*) field));
			}
		}
	}

	ut_ad(dtuple_check_typed(ref));
	if (UNIV_LIKELY_NULL(heap)) {
		mem_heap_free(heap);
	}
}

/***********************************************************************
From a row build a row reference with which we can search the clustered
index record. */

void
row_build_row_ref_from_row(
/*=======================*/
	dtuple_t*	ref,	/* in/out: row reference built; see the
				NOTE below! ref must have the right number
				of fields! */
	dict_table_t*	table,	/* in: table */
	dtuple_t*	row)	/* in: row
				NOTE: the data fields in ref will point
				directly into data of this row */
{
	dict_index_t*	clust_index;
	ulint		ref_len;
	ulint		i;

	ut_ad(ref && table && row);

	clust_index = dict_table_get_first_index(table);

	ref_len = dict_index_get_n_unique(clust_index);

	ut_ad(ref_len == dtuple_get_n_fields(ref));

	for (i = 0; i < ref_len; i++) {
		const dict_col_t*	col;
		dict_field_t*		field;
		dfield_t*		dfield;
		dfield_t*		dfield2;

		dfield = dtuple_get_nth_field(ref, i);

		field = dict_index_get_nth_field(clust_index, i);

		col = dict_field_get_col(field);

		dfield2 = dtuple_get_nth_field(row, dict_col_get_no(col));

		dfield_copy(dfield, dfield2);

		if (field->prefix_len > 0
		    && dfield->len != UNIV_SQL_NULL) {

			dfield->len = dtype_get_at_most_n_mbchars(
				col->prtype, col->mbminlen, col->mbmaxlen,
				field->prefix_len, dfield->len, dfield->data);
		}
	}

	ut_ad(dtuple_check_typed(ref));
}

/*******************************************************************
Searches the clustered index record for a row, if we have the row reference. */

ibool
row_search_on_row_ref(
/*==================*/
				/* out: TRUE if found */
	btr_pcur_t*	pcur,	/* in/out: persistent cursor, which must
				be closed by the caller */
	ulint		mode,	/* in: BTR_MODIFY_LEAF, ... */
	dict_table_t*	table,	/* in: table */
	dtuple_t*	ref,	/* in: row reference */
	mtr_t*		mtr)	/* in: mtr */
{
	ulint		low_match;
	rec_t*		rec;
	dict_index_t*	index;

	ut_ad(dtuple_check_typed(ref));

	index = dict_table_get_first_index(table);

	ut_a(dtuple_get_n_fields(ref) == dict_index_get_n_unique(index));

	btr_pcur_open(index, ref, PAGE_CUR_LE, mode, pcur, mtr);

	low_match = btr_pcur_get_low_match(pcur);

	rec = btr_pcur_get_rec(pcur);

	if (page_rec_is_infimum(rec)) {

		return(FALSE);
	}

	if (low_match != dtuple_get_n_fields(ref)) {

		return(FALSE);
	}

	return(TRUE);
}

/*************************************************************************
Fetches the clustered index record for a secondary index record. The latches
on the secondary index record are preserved. */

rec_t*
row_get_clust_rec(
/*==============*/
				/* out: record or NULL, if no record found */
	ulint		mode,	/* in: BTR_MODIFY_LEAF, ... */
	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 */
{
	mem_heap_t*	heap;
	dtuple_t*	ref;
	dict_table_t*	table;
	btr_pcur_t	pcur;
	ibool		found;
	rec_t*		clust_rec;

	ut_ad((index->type & DICT_CLUSTERED) == 0);

	table = index->table;

	heap = mem_heap_create(256);

	ref = row_build_row_ref(ROW_COPY_POINTERS, index, rec, heap);

	found = row_search_on_row_ref(&pcur, mode, table, ref, mtr);

	clust_rec = found ? btr_pcur_get_rec(&pcur) : NULL;

	mem_heap_free(heap);

	btr_pcur_close(&pcur);

	*clust_index = dict_table_get_first_index(table);

	return(clust_rec);
}

/*******************************************************************
Searches an index record. */

ibool
row_search_index_entry(
/*===================*/
				/* out: TRUE if found */
	dict_index_t*	index,	/* in: index */
	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 */
{
	ulint	n_fields;
	ulint	low_match;
	rec_t*	rec;

	ut_ad(dtuple_check_typed(entry));

	btr_pcur_open(index, entry, PAGE_CUR_LE, mode, pcur, mtr);
	low_match = btr_pcur_get_low_match(pcur);

	rec = btr_pcur_get_rec(pcur);

	n_fields = dtuple_get_n_fields(entry);

	if (page_rec_is_infimum(rec)) {

		return(FALSE);
	}

	if (low_match != n_fields) {
		/* Not found */

		return(FALSE);
	}

	return(TRUE);
}