You need at least version 5.5.3 of MySQL. Check your version number before you proceed:

mysql --version

1: Edit MySQL settings

1.1: Edit your MySQL config file:

sudo vi /etc/mysql/my.cnf

1.2: Add these lines in the [mysqld] section:

innodb_large_prefix=true
innodb_file_format=barracuda
innodb_file_per_table=true

1.3: To load the new settings, restart MySQL:

sudo service mysql restart

2: Convert database

Before you begin:

• You will need drush installed on your server. Click here for instructions
• Make backups of your databases

2.1: Download script

drush @none dl utf8mb4_convert-7.x

2.2: Go to your Drupal root

cd /var/www/html

2.3: Put your site into maintenance mode

drush vset maintenance_mode 1

2.4: Run the script

drush utf8mb4-convert-databases

2.5: Update settings.php

Open settings.php in your favorite text editor:

vi /var/www/html/sites/default/settings.php

Add these lines to your database array:

'charset' => 'utf8mb4',
'collation' => 'utf8mb4_general_ci',

It should look like this:

$databases['default']['default'] = array(
  'driver' => 'mysql',
  'database' => 'databasename',
  'username' => 'username',
  'password' => 'password',
  'host' => 'localhost',
  'charset' => 'utf8mb4',
  'collation' => 'utf8mb4_general_ci',
);

2.6: Take your site out of maintenance mode:

drush vset maintenance_mode 0

Enjoy the emoji support!
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