This is how…

On mysql set your table(s)’s filed(s) to utf8mb4_general_ci.

codeigniter config/database.php

$db['default']['char_set'] = 'utf8mb4';
$db['default']['dbcollat'] = 'utf8mb4_general_ci';

Resources

https://stackoverflow.com/questions/10957238/incorrect-string-value-when-trying-to-insert-utf-8-into-mysql-via-jdbc

https://stackoverflow.com/questions/16828197/displaying-utf8-character-on-codeigniter