WordPress Secure your installation Set a custom prefix for WordPress tables
Example
When you install WordPress to your server, the installation script will place a prefix in front of all the WordPress MySQL table names. This prefix is set to 'wp_' by default. The WordPress posts table will be called wp_posts for example. By changing the table prefix you can create some security by obscurity. This way when a hacker attempts SQL injection attacks, they will have to guess the prefix of your table rather than just using 'wp_'. You can set this prefix to be whatever you like.
Set Prefix in New WordPress Installation
If using famous 5 minute installation Change prefix in field during installation.
If installing via WordPress CLI use the following command:
// set other variables above, or substitute your strings in.
WP_DBPREFIX=foo
wp core config --dbname="$MYSQL_DBNAME" --dbuser="$MYSQL_USERNAME" --dbpass="$MYSQL_PASS" --dbprefix="$WP_DBPREFIX"_ --locale=en_AU
Change Prefix in Existing Installation
Changing the prefix is a little more difficult. Firstly use a FTP program like FileZilla to edit the wp-config.php file. Change the entry $table_prefix = 'wp_'; to $table_prefix = 'foo_'; substituting 'foo' for your desired prefix.
Next we'll need to edit the database. If you have access to phpMyAdmin, login and do the following:
- Select the WordPress database
- Select all tables and in the dropdown select replace table prefix.
- In "From" type 'wp_'. In "To" type your prefix, 'foo_' in this example and press "Submit".
- Tables should now look like this:
If you can't use phpMyAdmin then use the following MySQL command:
RENAME table `wp_comments` TO `foo_comments`
You'll need to run that command for each table, substituting 'comments' for the other table names.
Next we need to change a few entries in some tables. Run this query on the 'foo_options' table
SELECT * FROM foo_options WHERE option_name LIKE '%user_roles%'
A entry with option_name of 'wp_user_roles' should appear. In that entry change the 'option_name' entry from wp_user_roles to foo_user_roles.
Then open up 'foo_usermeta' table and find every entry with 'wp_' at the front.
and change it to 'foo_'. The number of entries you must change will depend on how many users you have.
That should be all you need to change the prefix in an existing installation
