Functions
bool	create_temporary_schemas (THD thd, Object_id mysql_schema_id, Object_id target_table_schema_id, String_type target_table_schema_name, Object_id *actual_table_schema_id)

void	establish_table_name_sets (std::set< String_type > create_set, std::set< String_type > remove_set)

bool	update_meta_data (THD *thd)
	Adjust metadata in source DD tables in mysql schema. More...

bool	migrate_meta_data (THD *thd, const std::set< String_type > &create_set, const std::set< String_type > &remove_set)
	Copy meta data from the actual tables to the target tables. More...

bool	update_object_ids (THD *thd, const std::set< String_type > &create_set, const std::set< String_type > &remove_set, Object_id mysql_schema_id, Object_id target_table_schema_id, const String_type &target_table_schema_name, Object_id actual_table_schema_id)

Function Documentation

◆ create_temporary_schemas()

bool dd::anonymous_namespace{dd.cc}::create_temporary_schemas	(	THD *	thd,
		Object_id *	mysql_schema_id,
		Object_id *	target_table_schema_id,
		String_type *	target_table_schema_name,
		Object_id *	actual_table_schema_id
	)

◆ establish_table_name_sets()

void dd::anonymous_namespace{dd.cc}::establish_table_name_sets	(	std::set< String_type > *	create_set,
		std::set< String_type > *	remove_set
	)

◆ migrate_meta_data()

bool dd::anonymous_namespace{dd.cc}::migrate_meta_data	(	THD *	thd,
		const std::set< String_type > &	create_set,
		const std::set< String_type > &	remove_set
	)

Copy meta data from the actual tables to the target tables.

The default is to copy all data. This is sufficient if we e.g. add a new index in the new DD version. If there are changes to the table columns, e.g. if we add or remove a column, we must add code to handle each case specifically. Suppose e.g. we add a new column to allow defining a default tablespace for each schema, and store the tablespace id in that column. Then, we could migrate the meta data for 'schemata' and set a default value for all existing schemas:

... migrated_set.insert("schemata"); if (dd::execute_query(thd, "INSERT INTO schemata " "SELECT id, catalog_id, name, default_collation_id, 1, " " created, last_altered, options FROM mysql.schemata")) ...

The code block above would go into the 'Version dependent migration' part of the function below.

Parameters

thd	Thread context.
create_set	Set of new or modified tables to be created.
remove_set	Set of abandoned or modified tables to be removed.

Returns: false if success. otherwise true.

◆ update_meta_data()

bool dd::anonymous_namespace{dd.cc}::update_meta_data ( THD * thd )

Adjust metadata in source DD tables in mysql schema.

This is done by mostly executing UPDATE queries on them, but we do not migrate data to destination DD tables.