4.3.3 Connecting using Unix Sockets and Windows Named Pipes

On Unix, MySQL Shell connections default to using Unix sockets when the following conditions are met:

• A TCP port is not specified.

• A host name is not specified or it is equal to localhost.

• The --socket or -S option is specified, with or without a path to a socket file.

If you specify --socket with no value and no equal sign, or -S without a value, the default Unix socket file for the protocol is used. If you specify a path to an alternative Unix socket file, that socket file is used.

If a host name is specified but it is not localhost, a TCP connection is established instead. In this case, if a TCP port is not specified the default value of 3306 is used.

On Windows, for MySQL Shell connections using classic MySQL protocol, if you specify the host name as a period (.), MySQL Shell connects using a named pipe.

• If you are connecting using a URI-like connection string, specify user@.

• If you are connecting using key-value pairs, specify {"host": "."}

• If you are connecting using individual parameters, specify --host=. or -h .

By default, the pipe name MySQL is used. You can specify an alternative named pipe using the --socket option or as part of the URI-like connection string.

In URI-like strings, the path to a Unix socket file or Windows named pipe must be encoded, using either percent encoding or by surrounding the path with parentheses. Parentheses eliminate the need to percent encode characters such as the / directory separator character. If the path to a Unix socket file is included in a URI-like string as part of the query string, the leading slash must be percent encoded, but if it replaces the host name, the leading slash must not be percent encoded, as shown in the following examples:

mysql-js> \connect user@localhost?socket=%2Ftmp%2Fmysql.sock
mysql-js> \connect user@localhost?socket=(/tmp/mysql.sock)
mysql-js> \connect user@/tmp%2Fmysql.sock 
mysql-js> \connect user@(/tmp/mysql.sock)

On Windows only, the named pipe must be prepended with the characters \\.\ as well as being either encoded using percent encoding or surrounded with parentheses, as shown in the following examples:

(\\.\named:pipe)
\\.\named%3Apipe

Important

On Windows, if one or more MySQL Shell sessions are connected to a MySQL Server instance using a named pipe and you need to shut down the server, you must first close the MySQL Shell sessions. Sessions that are still connected in this way can cause the server to hang during the shutdown procedure. If this does happen, exit MySQL Shell and the server will continue with the shutdown procedure.

For more information on connecting with Unix socket files and Windows named pipes, see Connecting to the MySQL Server Using Command Options and Connecting to the Server Using URI-Like Strings or Key-Value Pairs.