One, the socket file
The socket file was introduced when the MySQL communication method was introduced: https://blog.csdn.net/qq_41453285/article/details/104083287
Local connection to MySQL under the UNIX system can use the UNIX domain socket method. This method Need a socket file The
socket file can be controlled by the parameter socket, as shown below:
show variables like 'socket'\G;
Two, pid file
- When the MySQL instance starts, will own process ID will be written to a file - the file is pid file
- The file can be controlled by the parameter pid_file The , the default directory is located in the database:
show variables like 'pid_file'\G;
Three, table structure definition file
Because of the architecture of the MySQL plug-in storage engine, the storage of MySQL data is based on tables, and each table will have a corresponding file. But no matter what storage engine is used, MySQL has a file with the suffix frm. This file records the table structure definition of the table.
frm is also used to store the definition of the view. If the user creates a v_a view, the corresponding will Generate a v_a.frm file to record the definition of the view. The file is a text file and can be viewed directly using the cat command
