Error establishing a database connection
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WordPress is a sophisticated framework and a lot of help available online. Please have a look in your wp-config.php and also check the followings to make sure that configuration is correct.
1-
/** MySQL hostname */
define(‘DB_HOST’, ‘localhost’);
:: Normally this constant remain as it is as localhost, make sure that your phpmyadmin referring to the same host.
2-
/** MySQL database username */
define(‘DB_USER’, ‘yourmysqluser’);
:: It has prefix of your domain name sometimes and mostly it has first eight letters of your domain with underscore. You can check it from you cpanel.
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By clicking on MySql Databases, you can have a look on existing databases and users.
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3-
/** MySQL database password */
define(‘DB_PASSWORD’, ‘yourmysqlpassword’);
:: You can not obviously reset your password, just remove exisitng user and create a new one. And don’t forget to add that user to the required database, it means that you are giving that user specific or all privillages for DQL, DML etc.
4-
Once you have created or checked the username, password and database etc. Now access phpmyadmin from your cpanel.
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And verify that do you putting DB_HOST & DB_NAME correctly?
If everything is correct but still wordpress is displaying the same error, go to your wp-config.php and check do the followings:
1- Try to connect to your database by simple php mysql_connect() function.
2- Try to echo your constants which are DB_HOST, DB_NAME etc, are they displaying the correct information?
3- Hopefully you will get your problem resolved, if not yet then try a different copy of wordpress to install again. Or finally you can have a look on your hosting as well, sometimes we get PHP running fine but hostings do have separate databases servers. Hosting support will guide you regarding this. Error establishing a database connection is obviously a simple but can make trouble when it prevents our website to be displayed just after uploading it.
Last updated: March 19, 2014