row0upd.c

这是linux下运行的mysql软件包,可用于linux 下安装 php + mysql + apach 的网络配置

	ut_ad(update && index);

	n_unique = dict_index_get_n_unique(index);
	n_upd_fields = upd_get_n_fields(update);

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

		ind_field = dict_index_get_nth_field(index, i);
		col = dict_field_get_col(ind_field);
		col_pos = dict_col_get_clust_pos(col);
		col_no = dict_col_get_no(col);

		for (j = 0; j < n_upd_fields; j++) {

			upd_field = upd_get_nth_field(update, j);

			/* Note that if the index field is a column prefix
			then it may be that row does not contain an externally
			stored part of the column value, and we cannot compare
			the datas */

			if (col_pos == upd_field->field_no
			    && (row == NULL
			        || ind_field->prefix_len > 0
				|| !dfield_datas_are_binary_equal(
					dtuple_get_nth_field(row, col_no),
						&(upd_field->new_val)))) {
				return(TRUE);
			}
		}
	}

	return(FALSE);
}

/***************************************************************
Checks if an update vector changes an ordering field of an index record.
NOTE: we compare the fields as binary strings! */

ibool
row_upd_changes_some_index_ord_field_binary(
/*========================================*/
				/* out: TRUE if update vector may change
				an ordering field in an index record */
	dict_table_t*	table,	/* in: table */
	upd_t*		update)	/* in: update vector for the row */
{
	upd_field_t*	upd_field;
	dict_index_t*	index;
	ulint		i;
	
	index = dict_table_get_first_index(table);
	
	for (i = 0; i < upd_get_n_fields(update); i++) {

		upd_field = upd_get_nth_field(update, i);

		if (dict_field_get_col(dict_index_get_nth_field(index,
						upd_field->field_no))
		    ->ord_part) {

		    	return(TRUE);
		}
	}
	
	return(FALSE);
}

/***************************************************************
Checks if an update vector changes some of the first ordering fields of an
index record. This is only used in foreign key checks and we can assume
that index does not contain column prefixes. */
static
ibool
row_upd_changes_first_fields_binary(
/*================================*/
				/* out: TRUE if changes */
	dtuple_t*	entry,	/* in: index entry */
	dict_index_t*	index,	/* in: index of entry */
	upd_t*		update,	/* in: update vector for the row */
	ulint		n)	/* in: how many first fields to check */
{
	upd_field_t*	upd_field;
	dict_field_t*	ind_field;
	dict_col_t*	col;
	ulint		n_upd_fields;
	ulint		col_pos;
	ulint		i, j;
	
	ut_a(update && index);
	ut_a(n <= dict_index_get_n_fields(index));
	
	n_upd_fields = upd_get_n_fields(update);

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

		ind_field = dict_index_get_nth_field(index, i);
		col = dict_field_get_col(ind_field);
		col_pos = dict_col_get_clust_pos(col);

		ut_a(ind_field->prefix_len == 0);

		for (j = 0; j < n_upd_fields; j++) {

			upd_field = upd_get_nth_field(update, j);

			if (col_pos == upd_field->field_no
			    && !dfield_datas_are_binary_equal(
					     dtuple_get_nth_field(entry, i),
					     &(upd_field->new_val))) {
				return(TRUE);
			}
		}
	}

	return(FALSE);
}

/*************************************************************************
Copies the column values from a record. */
UNIV_INLINE
void
row_upd_copy_columns(
/*=================*/
	rec_t*		rec,	/* in: record in a clustered index */
	const ulint*	offsets,/* in: array returned by rec_get_offsets() */
	sym_node_t*	column)	/* in: first column in a column list, or
				NULL */
{
	byte*	data;
	ulint	len;

	while (column) {
		data = rec_get_nth_field(rec, offsets,
					column->field_nos[SYM_CLUST_FIELD_NO],
									&len);
		eval_node_copy_and_alloc_val(column, data, len);

		column = UT_LIST_GET_NEXT(col_var_list, column);
	}
}

/*************************************************************************
Calculates the new values for fields to update. Note that row_upd_copy_columns
must have been called first. */
UNIV_INLINE
void
row_upd_eval_new_vals(
/*==================*/
	upd_t*	update)	/* in: update vector */
{
	que_node_t*	exp;
	upd_field_t*	upd_field;
	ulint		n_fields;
	ulint		i;

	n_fields = upd_get_n_fields(update);

	for (i = 0; i < n_fields; i++) {
		upd_field = upd_get_nth_field(update, i);

		exp = upd_field->exp;

		eval_exp(exp);

		dfield_copy_data(&(upd_field->new_val), que_node_get_val(exp));
	}
}

/***************************************************************
Stores to the heap the row on which the node->pcur is positioned. */
static
void
row_upd_store_row(
/*==============*/
	upd_node_t*	node)	/* in: row update node */
{
	dict_index_t*	clust_index;
	upd_t*		update;
	rec_t*		rec;
	mem_heap_t*	heap		= NULL;
	ulint		offsets_[REC_OFFS_NORMAL_SIZE];
	const ulint*	offsets;
	*offsets_ = (sizeof offsets_) / sizeof *offsets_;

	ut_ad(node->pcur->latch_mode != BTR_NO_LATCHES);

	if (node->row != NULL) {
		mem_heap_empty(node->heap);
		node->row = NULL;
	}
	
	clust_index = dict_table_get_first_index(node->table);

	rec = btr_pcur_get_rec(node->pcur);
	
	offsets = rec_get_offsets(rec, clust_index, offsets_,
						ULINT_UNDEFINED, &heap);
	node->row = row_build(ROW_COPY_DATA, clust_index, rec, offsets,
								node->heap);
	node->ext_vec = mem_heap_alloc(node->heap, sizeof(ulint)
					* rec_offs_n_fields(offsets));
	if (node->is_delete) {
		update = NULL;
	} else {
		update = node->update;
	}
	
	node->n_ext_vec = btr_push_update_extern_fields(node->ext_vec,
						offsets, update);
	if (UNIV_LIKELY_NULL(heap)) {
		mem_heap_free(heap);
	}
}

/***************************************************************
Updates a secondary index entry of a row. */
static
ulint
row_upd_sec_index_entry(
/*====================*/
				/* out: DB_SUCCESS if operation successfully
				completed, else error code or DB_LOCK_WAIT */
	upd_node_t*	node,	/* in: row update node */
	que_thr_t*	thr)	/* in: query thread */
{
	ibool		check_ref;
	ibool		found;
	dict_index_t*	index;
	dtuple_t*	entry;
	btr_pcur_t	pcur;
	btr_cur_t*	btr_cur;
	mem_heap_t*	heap;
	rec_t*		rec;
	ulint		err	= DB_SUCCESS;
	mtr_t		mtr;
	trx_t*		trx	= thr_get_trx(thr);

	index = node->index;
	
	check_ref = row_upd_index_is_referenced(index, trx);

	heap = mem_heap_create(1024);

	/* Build old index entry */
	entry = row_build_index_entry(node->row, index, heap);

	log_free_check();
	mtr_start(&mtr);
	
	found = row_search_index_entry(index, entry, BTR_MODIFY_LEAF, &pcur,
									&mtr);
	btr_cur = btr_pcur_get_btr_cur(&pcur);

	rec = btr_cur_get_rec(btr_cur);

	if (UNIV_UNLIKELY(!found)) {
		fputs("InnoDB: error in sec index entry update in\n"
			"InnoDB: ", stderr);
		dict_index_name_print(stderr, trx, index);
		fputs("\n"
			"InnoDB: tuple ", stderr);
		dtuple_print(stderr, entry);
		fputs("\n"
			"InnoDB: record ", stderr);
		rec_print(stderr, rec, index);
		putc('\n', stderr);

		trx_print(stderr, trx, 0);

		fputs("\n"
"InnoDB: Submit a detailed bug report to http://bugs.mysql.com\n", stderr);
	} else {
 	  	/* Delete mark the old index record; it can already be
          	delete marked if we return after a lock wait in
          	row_ins_index_entry below */

		if (!rec_get_deleted_flag(rec, index->table->comp)) {
			err = btr_cur_del_mark_set_sec_rec(0, btr_cur, TRUE,
								thr, &mtr);
			if (err == DB_SUCCESS && check_ref) {
			    	
				/* NOTE that the following call loses
				the position of pcur ! */
				err = row_upd_check_references_constraints(
							node,
							&pcur, index->table,
							index, thr, &mtr);
				if (err != DB_SUCCESS) {

					goto close_cur;
				}
			}

	  	}
	}
close_cur:
	btr_pcur_close(&pcur);
	mtr_commit(&mtr);

	if (node->is_delete || err != DB_SUCCESS) {

		mem_heap_free(heap);	

        	return(err);
	}

	/* Build a new index entry */
	row_upd_index_replace_new_col_vals(entry, index, node->update, NULL);

	/* Insert new index entry */
	err = row_ins_index_entry(index, entry, NULL, 0, thr);

	mem_heap_free(heap);	

        return(err);
}

/***************************************************************
Updates secondary index record if it is changed in the row update. This
should be quite rare in database applications. */
UNIV_INLINE
ulint
row_upd_sec_step(
/*=============*/
				/* out: DB_SUCCESS if operation successfully
				completed, else error code or DB_LOCK_WAIT */
	upd_node_t*	node,	/* in: row update node */
	que_thr_t*	thr)	/* in: query thread */
{
	ulint	err;

	ut_ad((node->state == UPD_NODE_UPDATE_ALL_SEC)
				|| (node->state == UPD_NODE_UPDATE_SOME_SEC));
	ut_ad(!(node->index->type & DICT_CLUSTERED));
	
	if (node->state == UPD_NODE_UPDATE_ALL_SEC
	    || row_upd_changes_ord_field_binary(node->row, node->index,
							   node->update)) {
		err = row_upd_sec_index_entry(node, thr);

		return(err);
	}

	return(DB_SUCCESS);
}

/***************************************************************
Marks the clustered index record deleted and inserts the updated version
of the record to the index. This function should be used when the ordering
fields of the clustered index record change. This should be quite rare in
database applications. */
static
ulint
row_upd_clust_rec_by_insert(
/*========================*/
				/* out: DB_SUCCESS if operation successfully
				completed, else error code or DB_LOCK_WAIT */
	upd_node_t*	node,	/* in: row update node */
	dict_index_t*	index,	/* in: clustered index of the record */
	que_thr_t*	thr,	/* in: query thread */
	ibool		check_ref,/* in: TRUE if index may be referenced in
				a foreign key constraint */
	mtr_t*		mtr)	/* in: mtr; gets committed here */
{
	mem_heap_t*	heap	= NULL;
	btr_pcur_t*	pcur;
	btr_cur_t*	btr_cur;
	trx_t*		trx;
	dict_table_t*	table;
	dtuple_t*	entry;
	ulint		err;
	
	ut_ad(node);
	ut_ad(index->type & DICT_CLUSTERED);

	trx = thr_get_trx(thr);
	table = node->table;
	pcur = node->pcur;
	btr_cur	= btr_pcur_get_btr_cur(pcur);
	
	if (node->state != UPD_NODE_INSERT_CLUSTERED) {
		ulint	offsets_[REC_OFFS_NORMAL_SIZE];
		*offsets_ = (sizeof offsets_) / sizeof *offsets_;

		err = btr_cur_del_mark_set_clust_rec(BTR_NO_LOCKING_FLAG,
						btr_cur, TRUE, thr, mtr);
		if (err != DB_SUCCESS) {
			mtr_commit(mtr);
			return(err);
		}

		/* Mark as not-owned the externally stored fields which the new
		row inherits from the delete marked record: purge should not
		free those externally stored fields even if the delete marked
		record is removed from the index tree, or updated. */

		btr_cur_mark_extern_inherited_fields(btr_cur_get_rec(btr_cur),
				rec_get_offsets(btr_cur_get_rec(btr_cur),
				dict_table_get_first_index(table), offsets_,
				ULINT_UNDEFINED, &heap), node->update, mtr);
		if (check_ref) {
			/* NOTE that the following call loses
			the position of pcur ! */
			err = row_upd_check_references_constraints(node,
							pcur, table,
							index, thr, mtr);
			if (err != DB_SUCCESS) {
				mtr_commit(mtr);
				if (UNIV_LIKELY_NULL(heap)) {
					mem_heap_free(heap);
				}
				return(err);
			}
		}

	} 

	mtr_commit(mtr);

	if (!heap) {
		heap = mem_heap_create(500);
	}
	node->state = UPD_NODE_INSERT_CLUSTERED;

	entry = row_build_index_entry(node->row, index, heap);

	row_upd_index_replace_new_col_vals(entry, index, node->update, NULL);
	
	row_upd_index_entry_sys_field(entry, index, DATA_TRX_ID, trx->id);
	
	/* If we return from a lock wait, for example, we may have
	extern fields marked as not-owned in entry (marked in the
	if-branch above). We must unmark them. */
	
	btr_cur_unmark_dtuple_extern_fields(entry, node->ext_vec,
							node->n_ext_vec);
	/* We must mark non-updated extern fields in entry as inherited,
	so that a possible rollback will not free them */
	
	btr_cur_mark_dtuple_inherited_extern(entry, node->ext_vec,
						node->n_ext_vec,
						node->update);
	
	err = row_ins_index_entry(index, entry, node->ext_vec,
						node->n_ext_vec, thr);
	mem_heap_free(heap);
	
	return(err);
}

/***************************************************************
Updates a clustered index record of a row when the ordering fields do
not change. */
static
ulint
row_upd_clust_rec(
/*==============*/
				/* out: DB_SUCCESS if operation successfully
				completed, else error code or DB_LOCK_WAIT */
	upd_node_t*	node,	/* in: row update node */
	dict_index_t*	index,	/* in: clustered index */
	que_thr_t*	thr,	/* in: query thread */
	mtr_t*		mtr)	/* in: mtr; gets committed here */
{
	big_rec_t*	big_rec	= NULL;
	btr_pcur_t*	pcur;
	btr_cur_t*	btr_cur;
	ulint		err;
	
	ut_ad(node);
	ut_ad(index->type & DICT_CLUSTERED);

	pcur = node->pcur;
	btr_cur = btr_pcur_get_btr_cur(pcur);

	ut_ad(!rec_get_deleted_flag(btr_pcur_get_rec(pcur),
					index->table->comp));
	
	/* Try optimistic updating of the record, keeping changes within
	the page; we do not check locks because we assume the x-lock on the
	record to update */

	if (node->cmpl_info & UPD_NODE_NO_SIZE_CHANGE) {
		err = btr_cur_update_in_place(BTR_NO_LOCKING_FLAG,
						btr_cur, node->update,
						node->cmpl_info, thr, mtr);
	} else {
		err = btr_cur_optimistic_update(BTR_NO_LOCKING_FLAG,
						btr_cur, node->update,
						node->cmpl_info, thr, mtr);
	}

	mtr_commit(mtr);
	
	if (err == DB_SUCCESS) {

		return(err);
	}

	if (buf_LRU_buf_pool_running_out()) {
	
		return(DB_LOCK_TABLE_FULL);
	}
	/* We may have to modify the tree structure: do a pessimistic descent
	down the index tree */

	mtr_start(mtr);
	
	/* NOTE: this transaction has an s-lock or x-lock on the record and
	therefore other transactions cannot modify the record when we have no
	latch on the page. In addition, we assume that other query threads of
	the same transaction do not modify the record in the meantime.