dict0dict.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_fold_string(table->name), table);
	old_name = mem_heap_strdup(table->heap, table->name);
	table->name = mem_heap_strdup(table->heap, new_name);

	/* Add table to hash table of tables */
	HASH_INSERT(dict_table_t, name_hash, dict_sys->table_hash, fold,
								   table);
	dict_sys->size += (mem_heap_get_size(table->heap) - old_size);

	/* Update the table_name field in indexes */
	index = dict_table_get_first_index(table);

	while (index != NULL) {
		index->table_name = table->name;
		
		index = dict_table_get_next_index(index);
	}

	if (!rename_also_foreigns) {
		/* In ALTER TABLE we think of the rename table operation
		in the direction table -> temporary table (#sql...)
		as dropping the table with the old name and creating
		a new with the new name. Thus we kind of drop the
		constraints from the dictionary cache here. The foreign key
		constraints will be inherited to the new table from the
		system tables through a call of dict_load_foreigns. */
	
		/* Remove the foreign constraints from the cache */
		foreign = UT_LIST_GET_LAST(table->foreign_list);

		while (foreign != NULL) {
			dict_foreign_remove_from_cache(foreign);
			foreign = UT_LIST_GET_LAST(table->foreign_list);
		}

		/* Reset table field in referencing constraints */

		foreign = UT_LIST_GET_FIRST(table->referenced_list);

		while (foreign != NULL) {
			foreign->referenced_table = NULL;
			foreign->referenced_index = NULL;
		
			foreign = UT_LIST_GET_NEXT(referenced_list, foreign);
		}

		/* Make the list of referencing constraints empty */

		UT_LIST_INIT(table->referenced_list);
		
		return(TRUE);
	}

	/* Update the table name fields in foreign constraints, and update also
	the constraint id of new format >= 4.0.18 constraints. Note that at
	this point we have already changed table->name to the new name. */

	foreign = UT_LIST_GET_FIRST(table->foreign_list);

	while (foreign != NULL) {
		if (ut_strlen(foreign->foreign_table_name) <
						ut_strlen(table->name)) {
			/* Allocate a longer name buffer;
			TODO: store buf len to save memory */

			foreign->foreign_table_name = mem_heap_alloc(
					foreign->heap,
					ut_strlen(table->name) + 1);
		}

		strcpy(foreign->foreign_table_name, table->name);

		if (strchr(foreign->id, '/')) {
			ulint	db_len;
			char*	old_id;

			/* This is a >= 4.0.18 format id */

			old_id = mem_strdup(foreign->id);

			if (ut_strlen(foreign->id) > ut_strlen(old_name)
						+ ((sizeof dict_ibfk) - 1)
			    && 0 == ut_memcmp(foreign->id, old_name,
						ut_strlen(old_name))
			    && 0 == ut_memcmp(
					foreign->id + ut_strlen(old_name),
					dict_ibfk, (sizeof dict_ibfk) - 1)) {

				/* This is a generated >= 4.0.18 format id */

				if (ut_strlen(table->name) > ut_strlen(old_name)) {
					foreign->id = mem_heap_alloc(
					     foreign->heap,
						ut_strlen(table->name)
						+ ut_strlen(old_id) + 1);
				}
				
				/* Replace the prefix 'databasename/tablename'
				with the new names */
				strcpy(foreign->id, table->name);
				strcat(foreign->id,
						old_id + ut_strlen(old_name));
			} else {
				/* This is a >= 4.0.18 format id where the user
				gave the id name */
				db_len = dict_get_db_name_len(table->name) + 1;

				if (dict_get_db_name_len(table->name)
			    	    > dict_get_db_name_len(foreign->id)) {

					foreign->id = mem_heap_alloc(
					     foreign->heap,
				 	     db_len + ut_strlen(old_id) + 1);
				}

				/* Replace the database prefix in id with the
				one from table->name */
			
				ut_memcpy(foreign->id, table->name, db_len);

				strcpy(foreign->id + db_len,
						dict_remove_db_name(old_id));
			}

			mem_free(old_id);
		}

		foreign = UT_LIST_GET_NEXT(foreign_list, foreign);
	}

	foreign = UT_LIST_GET_FIRST(table->referenced_list);

	while (foreign != NULL) {
		if (ut_strlen(foreign->referenced_table_name) <
						ut_strlen(table->name)) {
			/* Allocate a longer name buffer;
			TODO: store buf len to save memory */

			foreign->referenced_table_name = mem_heap_alloc(
					foreign->heap,
					ut_strlen(table->name) + 1);
		}

		strcpy(foreign->referenced_table_name, table->name);

		foreign = UT_LIST_GET_NEXT(referenced_list, foreign);
	}

	return(TRUE);
}

/**************************************************************************
Change the id of a table object in the dictionary cache. This is used in
DISCARD TABLESPACE. */

void
dict_table_change_id_in_cache(
/*==========================*/
	dict_table_t*	table,	/* in: table object already in cache */
	dulint		new_id)	/* in: new id to set */
{
	ut_ad(table);
#ifdef UNIV_SYNC_DEBUG
	ut_ad(mutex_own(&(dict_sys->mutex)));
#endif /* UNIV_SYNC_DEBUG */
	ut_ad(table->magic_n == DICT_TABLE_MAGIC_N);

	/* Remove the table from the hash table of id's */

	HASH_DELETE(dict_table_t, id_hash, dict_sys->table_id_hash,
					ut_fold_dulint(table->id), table);
	table->id = new_id;

	/* Add the table back to the hash table */
	HASH_INSERT(dict_table_t, id_hash, dict_sys->table_id_hash,
					ut_fold_dulint(table->id), table);
}

/**************************************************************************
Removes a table object from the dictionary cache. */

void
dict_table_remove_from_cache(
/*=========================*/
	dict_table_t*	table)	/* in, own: table */
{
	dict_foreign_t*	foreign;
	dict_index_t*	index;
	ulint		size;
	ulint		i;
	
	ut_ad(table);
#ifdef UNIV_SYNC_DEBUG
	ut_ad(mutex_own(&(dict_sys->mutex)));
#endif /* UNIV_SYNC_DEBUG */
	ut_ad(table->magic_n == DICT_TABLE_MAGIC_N);

#if 0
	fputs("Removing table ", stderr);
	ut_print_name(stderr, table->name, ULINT_UNDEFINED);
	fputs(" from dictionary cache\n", stderr);
#endif

	/* Remove the foreign constraints from the cache */
	foreign = UT_LIST_GET_LAST(table->foreign_list);

	while (foreign != NULL) {
		dict_foreign_remove_from_cache(foreign);
		foreign = UT_LIST_GET_LAST(table->foreign_list);
	}

	/* Reset table field in referencing constraints */

	foreign = UT_LIST_GET_FIRST(table->referenced_list);

	while (foreign != NULL) {
		foreign->referenced_table = NULL;
		foreign->referenced_index = NULL;
		
		foreign = UT_LIST_GET_NEXT(referenced_list, foreign);
	}

	/* Remove the indexes from the cache */
	index = UT_LIST_GET_LAST(table->indexes);

	while (index != NULL) {
		dict_index_remove_from_cache(table, index);
		index = UT_LIST_GET_LAST(table->indexes);
	}

	/* Remove the columns of the table from the cache */
	for (i = 0; i < table->n_cols; i++) {
		dict_col_remove_from_cache(table,
					   dict_table_get_nth_col(table, i));
	}

	/* Remove table from the hash tables of tables */
	HASH_DELETE(dict_table_t, name_hash, dict_sys->table_hash,
					ut_fold_string(table->name), table);
	HASH_DELETE(dict_table_t, id_hash, dict_sys->table_id_hash,
					ut_fold_dulint(table->id), table);

	/* Remove table from LRU list of tables */
	UT_LIST_REMOVE(table_LRU, dict_sys->table_LRU, table);

	mutex_free(&(table->autoinc_mutex));

	size = mem_heap_get_size(table->heap);

	ut_ad(dict_sys->size >= size);

	dict_sys->size -= size;

	mem_heap_free(table->heap);
}

/**************************************************************************
Frees tables from the end of table_LRU if the dictionary cache occupies
too much space. Currently not used! */

void
dict_table_LRU_trim(void)
/*=====================*/
{
	dict_table_t*	table;
	dict_table_t*	prev_table;

	ut_error;

#ifdef UNIV_SYNC_DEBUG
	ut_ad(mutex_own(&(dict_sys->mutex)));
#endif /* UNIV_SYNC_DEBUG */

	table = UT_LIST_GET_LAST(dict_sys->table_LRU);

	while (table && (dict_sys->size >
			 buf_pool_get_max_size() / DICT_POOL_PER_VARYING)) {

		prev_table = UT_LIST_GET_PREV(table_LRU, table);

		if (table->mem_fix == 0) {
			dict_table_remove_from_cache(table);
		}

		table = prev_table;
	}
}

/**************************************************************************
Adds a column to the data dictionary hash table. */
static
void
dict_col_add_to_cache(
/*==================*/
	dict_table_t*	table,	/* in: table */
	dict_col_t*	col)	/* in: column */
{
	ulint	fold;

	ut_ad(table && col);
#ifdef UNIV_SYNC_DEBUG
	ut_ad(mutex_own(&(dict_sys->mutex)));
#endif /* UNIV_SYNC_DEBUG */
	ut_ad(table->magic_n == DICT_TABLE_MAGIC_N);
	
	fold = ut_fold_ulint_pair(ut_fold_string(table->name),
				  ut_fold_string(col->name));

	/* Look for a column with same table name and column name: error */
	{
		dict_col_t*	col2;
		HASH_SEARCH(hash, dict_sys->col_hash, fold, col2,
			(ut_strcmp(col->name, col2->name) == 0)
			&& (ut_strcmp((col2->table)->name, table->name)
							== 0));  
		ut_a(col2 == NULL);
	}

	HASH_INSERT(dict_col_t, hash, dict_sys->col_hash, fold, col);
}

/**************************************************************************
Removes a column from the data dictionary hash table. */
static
void
dict_col_remove_from_cache(
/*=======================*/
	dict_table_t*	table,	/* in: table */
	dict_col_t*	col)	/* in: column */
{
	ulint		fold;

	ut_ad(table && col);
#ifdef UNIV_SYNC_DEBUG
	ut_ad(mutex_own(&(dict_sys->mutex)));
#endif /* UNIV_SYNC_DEBUG */
	ut_ad(table->magic_n == DICT_TABLE_MAGIC_N);
	
	fold = ut_fold_ulint_pair(ut_fold_string(table->name),
				  ut_fold_string(col->name));

	HASH_DELETE(dict_col_t, hash, dict_sys->col_hash, fold, col);
}

/**************************************************************************
Repositions a column in the data dictionary hash table when the table name
changes. */
static
void
dict_col_reposition_in_cache(
/*=========================*/
	dict_table_t*	table,		/* in: table */
	dict_col_t*	col,		/* in: column */
	const char*	new_name)	/* in: new table name */
{
	ulint		fold;

	ut_ad(table && col);
#ifdef UNIV_SYNC_DEBUG
	ut_ad(mutex_own(&(dict_sys->mutex)));
#endif /* UNIV_SYNC_DEBUG */
	ut_ad(table->magic_n == DICT_TABLE_MAGIC_N);
	
	fold = ut_fold_ulint_pair(ut_fold_string(table->name),
				  ut_fold_string(col->name));

	HASH_DELETE(dict_col_t, hash, dict_sys->col_hash, fold, col);

	fold = ut_fold_ulint_pair(ut_fold_string(new_name),
				  ut_fold_string(col->name));
				  
	HASH_INSERT(dict_col_t, hash, dict_sys->col_hash, fold, col);
}

/**************************************************************************
Adds an index to the dictionary cache. */

ibool
dict_index_add_to_cache(
/*====================*/
				/* out: TRUE if success */
	dict_table_t*	table,	/* in: table on which the index is */
	dict_index_t*	index,	/* in, own: index; NOTE! The index memory
				object is freed in this function! */
	ulint		page_no)/* in: root page number of the index */
{
	dict_index_t*	new_index;
	dict_tree_t*	tree;
	dict_table_t*	cluster;
	dict_field_t*	field;
	ulint		n_ord;
	ibool		success;
	ulint		i;
	
	ut_ad(index);
#ifdef UNIV_SYNC_DEBUG
	ut_ad(mutex_own(&(dict_sys->mutex)));
#endif /* UNIV_SYNC_DEBUG */
	ut_ad(index->n_def == index->n_fields);
	ut_ad(index->magic_n == DICT_INDEX_MAGIC_N);
	
	ut_ad(mem_heap_validate(index->heap));

	{
		dict_index_t*	index2;
		index2 = UT_LIST_GET_FIRST(table->indexes);

		while (index2 != NULL) {
			ut_ad(ut_strcmp(index->name, index2->name) != 0);

			index2 = UT_LIST_GET_NEXT(indexes, index2);
		}

		ut_a(UT_LIST_GET_LEN(table->indexes) == 0
	      			|| (index->type & DICT_CLUSTERED) == 0);
	}

	success = dict_index_find_cols(table, index);

	if (!success) {
		dict_mem_index_free(index);

		return(FALSE);
	}
	
	/* Build the cache internal representation of the index,
	containing also the added system fields */

	if (index->type & DICT_CLUSTERED) {
		new_index = dict_index_build_internal_clust(table, index);
	} else {
		new_index = dict_index_build_internal_non_clust(table, index);
	}

	new_index->search_info = btr_search_info_create(new_index->heap);
	
	/* Set the n_fields value in new_index to the actual defined
	number of fields in the cache internal representation */

	new_index->n_fields = new_index->n_def;
	
	/* Add the new index as the last index for the table */

	UT_LIST_ADD_LAST(indexes, table->indexes, new_index);	
	new_index->table = table;
	new_index->table_name = table->name;

	/* Increment the ord_part counts in columns which are ordering */

	if (UNIV_UNLIKELY(index->type & DICT_UNIVERSAL)) {
		n_ord = new_index->n_fields;
	} else {
		n_ord = dict_index_get_n_unique(new_index);
	}

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

		field = dict_index_get_nth_field(new_index, i);

		dict_field_get_col(field)->ord_part++;
	}

	if (table->type == DICT_TABLE_CLUSTER_MEMBER) {
		/* The index tree is found from the cluster object */
	    
		cluster = dict_table_get_low(table->cluster_name);

		tree = dict_index_get_tree(
					UT_LIST_GET_FIRST(cluster->indexes));
		new_index->tree = tree;
	} else {
		/* Create an index tree memory object for the index */
		tree = dict_tree_create(new_index, page_no);
		ut_ad(tree);

		new_index->tree = tree;
	}

	if (!UNIV_UNLIKELY(new_index->type & DICT_UNIVERSAL)) {

		new_index->stat_n_diff_key_vals =
			mem_heap_alloc(new_index->heap,
				(1 + dict_index_get_n_unique(new_index))
				* sizeof(ib_longlong));
		/* Give some sensible values to stat_n_... in case we do
		not calculate statistics quickly enough */

		for (i = 0; i <= dict_index_get_n_unique(new_index); i++) {

			new_index->stat_n_diff_key_vals[i] = 100;
		}
	}
	
	/* Add the index to the list of indexes stored in the tree */
	UT_LIST_ADD_LAST(tree_indexes, tree->tree_indexes, new_index); 
	
	/* If the dictionary cache grows too big, trim the table LRU list */

	dict_sys->size += mem_heap_get_size(new_index->heap);
	/* dict_table_LRU_trim(); */

	dict_mem_index_free(index);