Revision as of 23:17, 19 December 2024

MySQL

MySQL is the best database management we know. That's what we use.

Survival kit

To know whether the database server is functional:

sudo service mysql status

SHOW databases;

is may be the most important command. It shows you what's in store.

Create a user

CREATE USER 'laussy' IDENTIFIED BY 'mypass';
GRANT ALL PRIVILEGES ON *.* TO 'laussy';

Export a database

From the command line:

mysqldump -u laussy -p wikilaussy > wikilaussy-24-jan-10.sql

to export the database data (wikilaussy-24-jan-10.sql, a readable file with very long lines) from the database structure (named wikilaussy) above.

Import a database

From the command line:

mysql -u laussy -p wikilaussy < wikilaussy-24-jan-10.sql

to import the database data (wikilaussy-24-jan-10.sql, a readable file with very long lines) into the database structure (named wikilaussy) above.

Change password

See [1]:

Stop the MySQL Server.

sudo /etc/init.d/mysql stop

If this does not work, try "mysql stop/waiting" instead~[2]

Start the mysqld configuration.

sudo mysqld --skip-grant-tables &

Login to MySQL as root.

mysql -u root mysql

Replace YOURNEWPASSWORD with your new password!

UPDATE user SET Password=PASSWORD('YOURNEWPASSWORD') WHERE User='root'; FLUSH PRIVILEGES; exit;

Would you encounter with a

ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock'

then turn to [3]

Recover from files

Normally you dump the database from the server itself. If, however, you only have access to the hard drive (bad things having happened to the system), you can restore the SQL database from files.

Links

• Linux command line and MySQL.