row0ins.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

#ifdef UNIV_DEBUG
	{
		page_t*	page = btr_cur_get_page(&cursor);
		rec_t*	first_rec = page_rec_get_next(
				page_get_infimum_rec(page));

		if (UNIV_LIKELY(first_rec != page_get_supremum_rec(page))) {
			ut_a(rec_get_n_fields(first_rec, index)
			== dtuple_get_n_fields(entry));
		}
	}
#endif

	n_unique = dict_index_get_n_unique(index);

	if (index->type & DICT_UNIQUE && (cursor.up_match >= n_unique
					 || cursor.low_match >= n_unique)) {

		if (index->type & DICT_CLUSTERED) {			 
			/* Note that the following may return also
			DB_LOCK_WAIT */

			err = row_ins_duplicate_error_in_clust(&cursor,
							entry, thr, &mtr);
			if (err != DB_SUCCESS) {

				goto function_exit;
			}
		} else {
			mtr_commit(&mtr);
			err = row_ins_scan_sec_index_for_duplicate(index,
								entry, thr);
			mtr_start(&mtr);

			if (err != DB_SUCCESS) {

				goto function_exit;
			}

			/* We did not find a duplicate and we have now
			locked with s-locks the necessary records to
			prevent any insertion of a duplicate by another
			transaction. Let us now reposition the cursor and
			continue the insertion. */
			
			btr_cur_search_to_nth_level(index, 0, entry,
					PAGE_CUR_LE, mode | BTR_INSERT,
					&cursor, 0, &mtr);
		}		
	}

	modify = row_ins_must_modify(&cursor);

	if (modify != 0) {
		/* There is already an index entry with a long enough common
		prefix, we must convert the insert into a modify of an
		existing record */

		if (modify == ROW_INS_NEXT) {
			rec = page_rec_get_next(btr_cur_get_rec(&cursor));

			btr_cur_position(index, rec, &cursor);
		}

		if (index->type & DICT_CLUSTERED) {
			err = row_ins_clust_index_entry_by_modify(mode,
							&cursor, &big_rec,
							entry,
							ext_vec, n_ext_vec,
							thr, &mtr);
		} else {
			err = row_ins_sec_index_entry_by_modify(mode, &cursor,
								entry,
								thr, &mtr);
		}
		
	} else {
		if (mode == BTR_MODIFY_LEAF) {
			err = btr_cur_optimistic_insert(0, &cursor, entry,
					&insert_rec, &big_rec, thr, &mtr);
		} else {
			ut_a(mode == BTR_MODIFY_TREE);
			if (buf_LRU_buf_pool_running_out()) {
	
				err = DB_LOCK_TABLE_FULL;

				goto function_exit;
			}
			err = btr_cur_pessimistic_insert(0, &cursor, entry,
					&insert_rec, &big_rec, thr, &mtr);
		}

		if (err == DB_SUCCESS) {
			if (ext_vec) {
				rec_set_field_extern_bits(insert_rec, index,
						ext_vec, n_ext_vec, &mtr);
			}
		}
	}

function_exit:
	mtr_commit(&mtr);

	if (big_rec) {
		rec_t*		rec;
		mtr_start(&mtr);
	
		btr_cur_search_to_nth_level(index, 0, entry, PAGE_CUR_LE,
					BTR_MODIFY_TREE, &cursor, 0, &mtr);
		rec = btr_cur_get_rec(&cursor);
		offsets = rec_get_offsets(rec, index, offsets,
					ULINT_UNDEFINED, &heap);

		err = btr_store_big_rec_extern_fields(index, rec,
						offsets, big_rec, &mtr);

		if (modify) {
			dtuple_big_rec_free(big_rec);
		} else {
			dtuple_convert_back_big_rec(index, entry, big_rec);
		}

		mtr_commit(&mtr);
	}

	if (UNIV_LIKELY_NULL(heap)) {
		mem_heap_free(heap);
	}
	return(err);
}

/*******************************************************************
Inserts an index entry to index. Tries first optimistic, then pessimistic
descent down the tree. If the entry matches enough to a delete marked record,
performs the insert by updating or delete unmarking the delete marked
record. */

ulint
row_ins_index_entry(
/*================*/
				/* out: DB_SUCCESS, DB_LOCK_WAIT,
				DB_DUPLICATE_KEY, or some other error code */
	dict_index_t*	index,	/* in: index */
	dtuple_t*	entry,	/* in: index entry to insert */
	ulint*		ext_vec,/* in: array containing field numbers of
				externally stored fields in entry, or NULL */
	ulint		n_ext_vec,/* in: number of fields in ext_vec */
	que_thr_t*	thr)	/* in: query thread */
{
	ulint	err;

	if (UT_LIST_GET_FIRST(index->table->foreign_list)) {
		err = row_ins_check_foreign_constraints(index->table, index,
								entry, thr);
		if (err != DB_SUCCESS) {

			return(err);
		}
	}

	/* Try first optimistic descent to the B-tree */

	err = row_ins_index_entry_low(BTR_MODIFY_LEAF, index, entry,
						ext_vec, n_ext_vec, thr);
	if (err != DB_FAIL) {

		return(err);
	}

	/* Try then pessimistic descent to the B-tree */

	err = row_ins_index_entry_low(BTR_MODIFY_TREE, index, entry,
						ext_vec, n_ext_vec, thr);
	return(err);
}

/***************************************************************
Sets the values of the dtuple fields in entry from the values of appropriate
columns in row. */
static
void
row_ins_index_entry_set_vals(
/*=========================*/
	dict_index_t*	index,	/* in: index */
	dtuple_t*	entry,	/* in: index entry to make */
	dtuple_t*	row)	/* in: row */
{
	dict_field_t*	ind_field;
	dfield_t*	field;
	dfield_t*	row_field;
	ulint		n_fields;
	ulint		i;
	dtype_t*        cur_type;

	ut_ad(entry && row);

	n_fields = dtuple_get_n_fields(entry);

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

		row_field = dtuple_get_nth_field(row, ind_field->col->ind);

		/* Check column prefix indexes */
		if (ind_field->prefix_len > 0
		    && dfield_get_len(row_field) != UNIV_SQL_NULL) {

			cur_type = dict_col_get_type(
				dict_field_get_col(ind_field));

			field->len = dtype_get_at_most_n_mbchars(cur_type,
				  ind_field->prefix_len,
				  dfield_get_len(row_field), row_field->data);
		} else {
		        field->len = row_field->len;
		}

		field->data = row_field->data;
	}
}

/***************************************************************
Inserts a single index entry to the table. */
static
ulint
row_ins_index_entry_step(
/*=====================*/
				/* out: DB_SUCCESS if operation successfully
				completed, else error code or DB_LOCK_WAIT */
	ins_node_t*	node,	/* in: row insert node */
	que_thr_t*	thr)	/* in: query thread */
{
	ulint	err;

	ut_ad(dtuple_check_typed(node->row));
	
	row_ins_index_entry_set_vals(node->index, node->entry, node->row);
	
	ut_ad(dtuple_check_typed(node->entry));

	err = row_ins_index_entry(node->index, node->entry, NULL, 0, thr);

	return(err);
}

/***************************************************************
Allocates a row id for row and inits the node->index field. */
UNIV_INLINE
void
row_ins_alloc_row_id_step(
/*======================*/
	ins_node_t*	node)	/* in: row insert node */
{
	dulint	row_id;
	
	ut_ad(node->state == INS_NODE_ALLOC_ROW_ID);
	
	if (dict_table_get_first_index(node->table)->type & DICT_UNIQUE) {

		/* No row id is stored if the clustered index is unique */

		return;
	}
	
	/* Fill in row id value to row */

	row_id = dict_sys_get_new_row_id();

	dict_sys_write_row_id(node->row_id_buf, row_id);
}

/***************************************************************
Gets a row to insert from the values list. */
UNIV_INLINE
void
row_ins_get_row_from_values(
/*========================*/
	ins_node_t*	node)	/* in: row insert node */
{
	que_node_t*	list_node;
	dfield_t*	dfield;
	dtuple_t*	row;
	ulint		i;
	
	/* The field values are copied in the buffers of the select node and
	it is safe to use them until we fetch from select again: therefore
	we can just copy the pointers */

	row = node->row; 

	i = 0;
	list_node = node->values_list;

	while (list_node) {
		eval_exp(list_node);

		dfield = dtuple_get_nth_field(row, i);
		dfield_copy_data(dfield, que_node_get_val(list_node));

		i++;
		list_node = que_node_get_next(list_node);
	}
}

/***************************************************************
Gets a row to insert from the select list. */
UNIV_INLINE
void
row_ins_get_row_from_select(
/*========================*/
	ins_node_t*	node)	/* in: row insert node */
{
	que_node_t*	list_node;
	dfield_t*	dfield;
	dtuple_t*	row;
	ulint		i;

	/* The field values are copied in the buffers of the select node and
	it is safe to use them until we fetch from select again: therefore
	we can just copy the pointers */

	row = node->row; 

	i = 0;
	list_node = node->select->select_list;

	while (list_node) {
		dfield = dtuple_get_nth_field(row, i);
		dfield_copy_data(dfield, que_node_get_val(list_node));

		i++;
		list_node = que_node_get_next(list_node);
	}
}
	
/***************************************************************
Inserts a row to a table. */

ulint
row_ins(
/*====*/
				/* out: DB_SUCCESS if operation successfully
				completed, else error code or DB_LOCK_WAIT */
	ins_node_t*	node,	/* in: row insert node */
	que_thr_t*	thr)	/* in: query thread */
{
	ulint	err;
	
	ut_ad(node && thr);

	if (node->state == INS_NODE_ALLOC_ROW_ID) {

		row_ins_alloc_row_id_step(node);
	
		node->index = dict_table_get_first_index(node->table);
		node->entry = UT_LIST_GET_FIRST(node->entry_list);

		if (node->ins_type == INS_SEARCHED) {

			row_ins_get_row_from_select(node);

		} else if (node->ins_type == INS_VALUES) {

			row_ins_get_row_from_values(node);
		}

		node->state = INS_NODE_INSERT_ENTRIES;
	}

	ut_ad(node->state == INS_NODE_INSERT_ENTRIES);

	while (node->index != NULL) {
		err = row_ins_index_entry_step(node, thr);
		
		if (err != DB_SUCCESS) {

			return(err);
		}

		node->index = dict_table_get_next_index(node->index);
		node->entry = UT_LIST_GET_NEXT(tuple_list, node->entry);
	}

	ut_ad(node->entry == NULL);
	
	node->state = INS_NODE_ALLOC_ROW_ID;
	
	return(DB_SUCCESS);
}

/***************************************************************
Inserts a row to a table. This is a high-level function used in SQL execution
graphs. */

que_thr_t*
row_ins_step(
/*=========*/
				/* out: query thread to run next or NULL */
	que_thr_t*	thr)	/* in: query thread */
{
	ins_node_t*	node;
	que_node_t*	parent;
	sel_node_t*	sel_node;
	trx_t*		trx;
	ulint		err;

	ut_ad(thr);
	
	trx = thr_get_trx(thr);

	trx_start_if_not_started(trx);
	
	node = thr->run_node;

	ut_ad(que_node_get_type(node) == QUE_NODE_INSERT);

	parent = que_node_get_parent(node);
	sel_node = node->select;

	if (thr->prev_node == parent) {
		node->state = INS_NODE_SET_IX_LOCK;
	}

	/* If this is the first time this node is executed (or when
	execution resumes after wait for the table IX lock), set an
	IX lock on the table and reset the possible select node. */

	if (node->state == INS_NODE_SET_IX_LOCK) {

		/* It may be that the current session has not yet started
		its transaction, or it has been committed: */
		
		if (UT_DULINT_EQ(trx->id, node->trx_id)) {
			/* No need to do IX-locking or write trx id to buf */

			goto same_trx;
		}	

		trx_write_trx_id(node->trx_id_buf, trx->id);

		err = lock_table(0, node->table, LOCK_IX, thr);

		if (err != DB_SUCCESS) {

			goto error_handling;
		}

		node->trx_id = trx->id;
	same_trx:				
		node->state = INS_NODE_ALLOC_ROW_ID;

		if (node->ins_type == INS_SEARCHED) {
			/* Reset the cursor */
			sel_node->state = SEL_NODE_OPEN;
 		
			/* Fetch a row to insert */
		
			thr->run_node = sel_node;
	
			return(thr);
		}
	}

	if ((node->ins_type == INS_SEARCHED)
				&& (sel_node->state != SEL_NODE_FETCH)) {

		ut_ad(sel_node->state == SEL_NODE_NO_MORE_ROWS);

		/* No more rows to insert */
		thr->run_node = parent;
	
		return(thr);
	}

	/* DO THE CHECKS OF THE CONSISTENCY CONSTRAINTS HERE */

	err = row_ins(node, thr);

error_handling:
	trx->error_state = err;

	if (err != DB_SUCCESS) {
		/* err == DB_LOCK_WAIT or SQL error detected */
		return(NULL);
	}

	/* DO THE TRIGGER ACTIONS HERE */

	if (node->ins_type == INS_SEARCHED) {
		/* Fetch a row to insert */
		
		thr->run_node = sel_node;
	} else {
		thr->run_node = que_node_get_parent(node);
	}

	return(thr);
}