When connecting to MySQL, it is a process of communication between a connection process and a MySQL database instance
The essence of communication is process communication
The ways of inter-process communication are : pipes, named pipes, shared memory, TCP/IP sockets, UNIX domain sockets, etc.
Two, TCP/IP socket connection
Between different machines , the client can use the mysql command to connect to the MySQL server. At this time, the TCP/IP socket is used.
Three, named pipes and shared memory
Named pipe
On Windows 2000, Windows XP, Windows 2003 and Windows Vista and above platforms, if two processes that require process communication are on the same server, you can use named pipes . The Microsoft SQL Server database is installed locally by default. The connection also uses named pipes
In the MySQL database, the --enable-named-pipe option must be enabled in the configuration file
Shared memory
In versions after MySQL 4.1, MySQL also provides a shared memory connection method, which is achieved by adding --shared-memory in the configuration file
If you want to use shared memory, when connecting, the MySQL client must also use the --protocol=memory option
Four, UNIX domain socket
UNIX domain sockets can only be used on one machine
The user can specify the path of the socket file in the configuration file , such as --socket=/tmp/mysql.sock
Demo case
View the location of the UNIX domain socket file
Exit the database, and then use the domain socket to connect to the database (when using the domain socket connection, you need to use the -S option to provide the UNIX domain socket file name, the -u option to provide the user name, the -p option to provide the user password,- I use mosaic to cover the p option)
