MySQL Cookbook

Starting and Terminating mysql

Problem

You want to start and stop the mysql program.

Solution

Invoke mysql from your command prompt to start it, specifying any connection parameters that may be necessary. To leave mysql, use a QUIT statement.

Discussion

To start the mysql program, try just typing its name at your command-line prompt. If mysql starts up correctly, you’ll see a short message, followed by a mysql> prompt that indicates the program is ready to accept queries. To illustrate, here’s what the welcome message looks like (to save space, I won’t show it in any further examples):

% mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 18427 to server version: 3.23.51-log

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql>

If mysql tries to start but exits immediately with an “access denied” message, you’ll need to specify connection parameters. The most commonly needed parameters are the host to connect to (the host where the MySQL server runs), your MySQL username, and a password. For example:

% mysql -h localhost -p -u cbuser
Enter password: cbpass

In general, I’ll show mysql commands in examples with no connection parameter options. I assume that you’ll supply any parameters that you need, either on the command line, or in an option file (Recipe 1.5) so that you don’t have to type them each time you invoke mysql.

If you don’t have a MySQL username and password, you need to obtain permission to use the MySQL server, as described earlier in Recipe 1.2.

The syntax and default values for the connection parameter options are shown in the following table. These options have both a single-dash short form and a double-dash long form.

Parameter type	Option syntax forms	Default value
Hostname	-h hostname--host=hostname	localhost
Username	-u username--user=username	Your login name
Password	-p--password	None

As the table indicates, there is no default password. To supply one, use --password or -p, then enter your password when mysql prompts you for it:

% mysql -pEnter password: ← enter your password here

If you like, you can specify the password directly on the command line by using either -ppassword (note that there is no space after the -p) or --password=password. I don’t recommend doing this on a multiple-user machine, because the password may be visible momentarily to other users who are running tools such as ps that report process information.

If you get an error message that mysql cannot be found or is an invalid command when you try to invoke it, that means your command interpreter doesn’t know where mysql is installed. See Recipe 1.8.

To terminate a mysql session, issue a QUIT statement:

mysql> QUIT

You can also terminate the session by issuing an EXIT statement or (under Unix) by typing Ctrl-D.

The way you specify connection parameters for mysql also applies to other MySQL programs such as mysqldump and mysqladmin. For example, some of the actions that mysqladmin can perform are available only to the MySQL root account, so you need to specify name and password options for that user:

% mysqladmin -p -u root shutdown
Enter password: