MySQL 8.4 Release Notes
30.4.4.1 创建synonym_db()过程
给定一个架构名称，这个过程创建一个同义名称架构，该架构包含对原始架构中的所有表和视图的引用。例如，可以使用该过程来创建一个短名称，以便引用一个长名称的架构（例如info而不是INFORMATION_SCHEMA）。
-
in_db_name VARCHAR(64): 需要创建同义名称架构的架构名称。 -
in_synonym VARCHAR(64): 为同义名称架构指定的名称。该架构不能已经存在。
mysql> SHOW DATABASES;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
| world |
+--------------------+
mysql> CALL sys.create_synonym_db('INFORMATION_SCHEMA', 'info');
+---------------------------------------+
| summary |
+---------------------------------------+
| Created 63 views in the info database |
+---------------------------------------+
mysql> SHOW DATABASES;
+--------------------+
| Database |
+--------------------+
| information_schema |
| info |
| mysql |
| performance_schema |
| sys |
| world |
+--------------------+
mysql> SHOW FULL TABLES FROM info;
+---------------------------------------+------------+
| Tables_in_info | Table_type |
+---------------------------------------+------------+
| character_sets | VIEW |
| collation_character_set_applicability | VIEW |
| collations | VIEW |
| column_privileges | VIEW |
| columns | VIEW |
...