在MySQL中创建表时生成的文件是什么（.opt，.frm，.MYD，.MYI）

When I create a database in MySQL and create a table called flat in it, 4 files are generated:

1. db.opt
2. flats.frm
3. flats.MYD
4. flats.MYI

This happens every time a table is created.

What are these files?

The file db.opt contains the database characteristics. It is updated every time the database is altered.

For the remaining 3 files:

• table.frm - Describes the table's format (it is created regardless of the storage engine being used)
• table.MYI - Contains the MyISAM table index information (created for MyISAM storage engine)
• table.MYD - Contains the MyISAM table data (created for MyISAM storage engine)