~ : sudo launchctl load -w /Library/LaunchDaemons/org.macports.mysql5.plist
Password:
 ~ : sudo launchctl load -w /Library/LaunchDaemons/org.macports.mysql5.plist
org.macports.mysql5: Already loaded
 ~ : sudo -u mysql mysql_install_db5
Installing MySQL system tables...
081017 15:23:05 [Warning] option 'max_join_size': unsigned value 18446744073709551615 adjusted to 4294967295
081017 15:23:05 [Warning] option 'max_join_size': unsigned value 18446744073709551615 adjusted to 4294967295
081017 15:23:05 [Warning] Setting lower_case_table_names=2 because file system for /opt/local/var/db/mysql5/ is case insensitive
OK
Filling help tables...
081017 15:23:05 [Warning] option 'max_join_size': unsigned value 18446744073709551615 adjusted to 4294967295
081017 15:23:05 [Warning] option 'max_join_size': unsigned value 18446744073709551615 adjusted to 4294967295
081017 15:23:05 [Warning] Setting lower_case_table_names=2 because file system for /opt/local/var/db/mysql5/ is case insensitive
OK

To start mysqld at boot time you have to copy
support-files/mysql.server to the right place for your system

PLEASE REMEMBER TO SET A PASSWORD FOR THE MySQL root USER !
To do so, start the server, then issue the following commands:
/opt/local/lib/mysql5/bin/mysqladmin -u root password 'new-password'
/opt/local/lib/mysql5/bin/mysqladmin -u root -h robby-russells-macbook-pro.local password 'new-password'

Alternatively you can run:
/opt/local/lib/mysql5/bin/mysql_secure_installation

which will also give you the option of removing the test
databases and anonymous user created by default.  This is
strongly recommended for production servers.

See the manual for more instructions.

You can start the MySQL daemon with:
cd /opt/local ; /opt/local/lib/mysql5/bin/mysqld_safe &

You can test the MySQL daemon with mysql-test-run.pl
cd mysql-test ; perl mysql-test-run.pl

Please report any problems with the /opt/local/lib/mysql5/bin/mysqlbug script!

The latest information about MySQL is available on the web at
http://www.mysql.com
Support MySQL by buying support/licenses at http://shop.mysql.com