5.7.4. Connecting to the MySQL Server
MySQL client programs generally expect you to specify certain
connection parameters when you want to access a MySQL server:
For example, the mysql client can be started
as follows from a command-line prompt (indicated here by
shell>):
shell> mysql -h host_name -u user_name -pyour_pass
Alternative forms of the -h,
-u, and -p options are
--host=host_name,
--user=user_name,
and
--password=your_pass.
Note that there is no space between
-p or --password= and the
password following it.
If you use a -p or --password
option but do not specify the password value, the client program
prompts you to enter the password. The password is not displayed
as you enter it. This is more secure than giving the password on
the command line. Any user on your system may be able to see a
password specified on the command line by executing a command
such as ps auxww. See
Section 5.8.6, “Keeping Your Password Secure”.
MySQL client programs use default values for any connection
parameter option that you do not specify:
The default hostname is localhost.
The default username is ODBC on Windows
and your Unix login name on Unix.
No password is supplied if neither -p nor
--passwordis given.
Thus, for a Unix user with a login name of
joe, all of the following commands are
equivalent:
shell> mysql -h localhost -u joe
shell> mysql -h localhost
shell> mysql -u joe
shell> mysql
Other MySQL clients behave similarly.
You can specify different default values to be used when you
make a connection so that you need not enter them on the command
line each time you invoke a client program. This can be done in
a couple of ways:
-
You can specify connection parameters in the
[client] section of an option file. The
relevant section of the file might look like this:
[client]
host=host_name
user=user_name
password=your_pass
Section 4.3.2, “Using Option Files”, discusses option files
further.
You can specify some connection parameters using environment
variables. The host can be specified for
mysql using
MYSQL_HOST. The MySQL username can be
specified using USER (this is for Windows
and NetWare only). The password can be specified using
MYSQL_PWD, although this is insecure; see
Section 5.8.6, “Keeping Your Password Secure”. For a list of
variables, see Appendix F, Environment Variables.
