MySQL has no limit on the number of databases. MySQL对数据库的数量没有限制。The underlying file system may have a limit on the number of directories.基础文件系统可能对目录的数量有限制。

MySQL has no limit on the number of tables. MySQL对表的数量没有限制。The underlying file system may have a limit on the number of files that represent tables. 底层文件系统可能对表示表的文件数量有限制。Individual storage engines may impose engine-specific constraints. 单个存储引擎可能会施加特定于引擎的约束。InnoDB permits up to 4 billion tables.InnoDB允许多达40亿个表。