Error Establishing a Database Connection

The “Error Establishing a Database Connection” is a critical WordPress error that means WordPress cannot connect to your database.

Here’s a step-by-step guide to fix it:

1. Check `wp-config.php` File

Make sure your database details are correct:

Open your website files via FTP or File Manager.
Locate the file: /public_html/wp-config.php
Check these lines:

define( 'DB_NAME', 'your_db_name' );
define( 'DB_USER', 'your_db_user' );
define( 'DB_PASSWORD', 'your_db_password' );
define( 'DB_HOST', 'localhost' ); // Usually "localhost"

Ensure values are correct. Ask your hosting provider if you’re not sure.

2. Test Database Access

Use phpMyAdmin or a simple script to test DB login:

<?php
$connection = mysqli_connect('localhost','your_db_user','your_db_password','your_db_name');
if ($connection) {
    echo 'Connected successfully!';
} else {
    die('Database connection failed: ' . mysqli_connect_error());
}
?>

If this fails → the issue is with credentials or the DB server.

3. Check with Hosting Provider

Ask them:

Is Mysql server up and running?
Is the DB username allowed access to that DB?

Sometimes the database server is temporarily down.

4. Repair WordPress Database

Add this line to wp-config.php:

define('WP_ALLOW_REPAIR', true);

Then go to:

https://yourdomain.com/wp-admin/maint/repair.php

Click: “Repair and Optimise Database”

After that, remove the line from wp-config.php.

5. Check for Corrupt Files

Re-upload a fresh copy of:

/wp-includes/
/wp-admin/

Don’t delete wp-content/ or wp-config.php.

6. Check Website Traffic (Too High)

If your site is under heavy traffic, your DB may crash.

Check with your host
Upgrade the hosting plan if needed

7. Check DB User Privileges

In phpMyAdmin, make sure:

The user has ALL PRIVILEGES on the database.

8. Restart Mysql Server

(For VPS or Dedicated Server)

Use SSH and type:

sudo service mysql restart