Part-DB.Part-DB-server/src/Doctrine/SQLiteRegexExtension.php

<?php

namespace App\Doctrine;

use Doctrine\Bundle\DoctrineBundle\EventSubscriber\EventSubscriberInterface;
use Doctrine\DBAL\Event\ConnectionEventArgs;
use Doctrine\DBAL\Events;
use Doctrine\DBAL\Platforms\SqlitePlatform;

/**
 * This subscriber is used to add the regexp operator to the SQLite platform.
 * As a PHP callback is called for every entry to compare it is most likely much slower than using regex on MySQL.
 * But as regex is not often used, this should be fine for most use cases, also it is almost impossible to implement a better solution.
 */
class SQLiteRegexExtension implements EventSubscriberInterface
{
    public function postConnect(ConnectionEventArgs $eventArgs): void
    {
        $connection = $eventArgs->getConnection();

        //We only execute this on SQLite databases
        if ($connection->getDatabasePlatform() instanceof SqlitePlatform) {
            $native_connection = $connection->getNativeConnection();

            //Ensure that the function really exists on the connection, as it is marked as experimental according to PHP documentation
            if($native_connection instanceof \PDO && method_exists($native_connection, 'sqliteCreateFunction' )) {
                $native_connection->sqliteCreateFunction('REGEXP', function ($pattern, $value) {
                    return (false !== mb_ereg($pattern, $value)) ? 1 : 0;
                });
            }
        }
    }

    public function getSubscribedEvents()
    {
        return[
            Events::postConnect
        ];
    }
}