Oracle 5.0, Справочное руководство

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Setting Environment Variables
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Similar issues can arise when specifying option values in option files. For example, consider a
my.cnf
file that contains the following:
[mysql]
host
user
When the
mysql
client reads this file, these entries are parsed as
--host
[266]
--user
[270] or
--host=--user
[266] , with the result shown here:
shell> mysql
ERROR 2005 (HY000): Unknown MySQL server host '--user' (1)
However, in option files, an equal sign is not assumed. Suppose the
my.cnf
file is as shown here:
[mysql]
user jon
Trying to start
mysql
in this case causes a different error:
shell> mysql
mysql: unknown option '--user jon'
A similar error would occur if you were to write
host tonfisk
in the option file rather than
host=tonfisk
. Instead, you must use the equals sign:
[mysql]
user=jon
Now the login attempt succeeds:
shell> mysql
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 5
Server version: 5.0.96 Source distribution
Type 'help;' or '\h' for help. Type '\c' to clear the buffer.
mysql> SELECT USER();
+---------------+
| USER() |
+---------------+
| jon@localhost |
+---------------+
1 row in set (0.00 sec)
This is not the same behavior as with the command line, where the equals sign is not required:
shell> mysql --user jon --host tonfisk
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 6
Server version: 5.0.96 Source distribution
Type 'help;' or '\h' for help. Type '\c' to clear the buffer.
mysql> SELECT USER();
+---------------+
| USER() |
+---------------+
| jon@tonfisk |
+---------------+
1 row in set (0.00 sec)
4.2.4. Setting Environment Variables
Environment variables can be set at the command prompt to affect the current invocation of your
command processor, or set permanently to affect future invocations. To set a variable permanently,