MySql index Myisam engine (non-clustered index)

Mysql internal file

If the table test_my is created with this Myisam engine, see the code for details:

CREATE TABLE `test_my` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `mame` varchar(100),
  PRIMARY KEY (`id`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8;

We will find three files test_my.frm, test_my.MYD, test_my.MYI in the D:\MySQL\mysql-5.7.13-winx64\data\ library name directory

test_my.frm: data structure type

test_my.MYD: data file

test_my.MYI: index file

Query process

When select * from test_my where id = 1 is executed, it will first find id=1 from the test_my.MYI file, and the corresponding data address addr, and then find a specific line of data in the test_my.MYD file according to addr

Diagram of the data structure of Mysql internal files