mysql Archives - Switched On Tech Design

June 8, 2017June 8, 2017

Importing a MySQL database with a new name where the original still exists

So you want to export your MySQL database then import it on the same server with a new name. I tried this several times and using the SOURCE command inside MySQL or just mysql -p < db.sql both resulted in the database re-importing over the original name. To fix that run:

sed -i 's/OLDDATABASENAME/NEWDBNAME/g' mysqldumpFile.sql

Then run:

mysql -p

create NEWDBNAME;

use NEWDBNAME;

SOURCE /path/to/sql/file

No need for a semicolon on the last line. Then check the success by:

show tables;

April 2, 2013March 30, 2013

MySQL: How to log in

If you’re unfamiliar with MySQL you may be following a guide which instructs you to log in as root without actually telling you how; use the following:

mysql -u root -p

This logs you in as the root user (-u signifying which user you want to log in as) and -p signifies that you are logging in with a password, which you will be prompted for after you enter the command. The MySQL root password is set when you install MySQL server.

March 3, 2013March 29, 2013

MySQL: How to create a database

To create a simple database (e.g. if you need to create one for a WordPress or Wiki install) use the following after logging in to MySQL as the root user:

create database [nameOfDatabase];

Don’t forget the ; at the end, or you’ll end up on a new line consisting of a > prompt waiting for more input. You can put the ; in then if you forgot to complete the command. An example of the above would be:

create database wikiDB;

…which would create the database named wikiDB. You should see the following on a successful command:

Query OK, 1 row affected (0.04 sec)

If that is all you had to do you can now exit MySQL by typing:

exit

…and you’re done!

January 9, 2013January 9, 2013

MySQL: Changing the root user’s password

If you need to change the MySQL root user’s password use the following from a command prompt:

mysqladmin -u root -p password NEWPASSWORD

Enter the current root password when prompted and replace NEWPASSWORD with the desired password. This should return you to the command prompt, and you can test whether it was successful by logging in:

mysql -u root -p

November 21, 2012November 20, 2012

How to change a user’s password in Mediawiki

If you have a wiki you may need to change a user’s password from time to time; you can do this from the back end quite easily. First, access mysql:

mysql -u root -p

show databases;

On our test system this shows all of our databases like so:

mysql> show databases; +——————–+ | Database +——————–+ | information_schema | mysql | performance_schema | press | test | wiki +——————–+ 6 rows in set (0.10 sec)

Select your wiki’s database:

USE wiki;

Replace “wiki” in the above with your own database’s name.

UPDATE user SET user_password = MD5(CONCAT(user_id, ‘-‘, MD5(‘newpasswordgoeshere’))) WHERE user_name = ‘usernameofuser’;

If this is successful you should get the following:

Query OK, 1 row affected (0.01 sec) Rows matched: 1 Changed: 1 Warnings: 0

If something has gone wrong (e.g. a non-existent username) you will get the following instead:

Query OK, 0 rows affected (0.03 sec) Rows matched: 0 Changed: 0 Warnings: 0

All done! To leave mysql just type “exit”.

November 16, 2012November 14, 2012

How To: Export all mysql databases for backup

This is a handy command for anyone using multiple mysql databases – it produces a single file which you can easily back up to elsewhere.

mysqldump -u root -p –all-databases > databasesBackup.sql

Note the two hyphens before “all”. This command creates the file databasesBackup.sql which contains the contents of all of your databases. This file can be easily rsync’d or scp’d elsewhere to create an offsite backup of your site’s databases.