and make sure you have a lot of backups- add this before your website define('WP_ALLOW_REPAIR', true); then go to this http://www.yoursite.com/wp-admin/maint/repair.php

WP-Config.php is probably the single most important file in your entire WordPress installation. This is where you specify the details for WordPress to connect your database. If you changed your root password, or the database user password, then you will need to change this file as well. First thing you should always check is if everything in your wp-config.php file is the same. 1 define('DB_NAME', 'database-name'); 2 define('DB_USER', 'database-username'); 3 define('DB_PASSWORD', 'database-password'); 4 define('DB_HOST', 'localhost'); Remember your DB_Host value might not always be localhost.

if that doesn't work try this

Test other sites on the same server to see if they are having the issue. If they are also getting the same error, then most definitely there is something wrong with your MySQL server. If you do not have any other site on this same hosting account simply go to your cPanel and try to access phpMyAdmin and connect the database. If you can connect, then we need to verify if your database user has sufficient permission. Create a new file called testconnection.php and paste the following code in it: view sourceprint? 1 <?php 2 $link = mysql_connect('localhost', 'root', 'password'); 3 if (!$link) { 4 die('Could not connect: ' . mysql_error()); 5 } 6 echo 'Connected successfully'; 7 mysql_close($link); 8 ?>