MYSQLI_OPT_LOCAL_INFILE

Is there a way to set this parameter directly in the config/database.php settings or should it be done another way?

Thanks

No, you cannot set in config/Database.php.

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You can get MySQLi object.

When CI4 MySQLi connection does not yet connect to MySQL server.
$db     = db_connect();
$mysqli = $db->connect();
d($mysqli);      // mysqli object

When CI4 MySQLi connection has already connected to MySQL server.
$db    = db_connect();
dd($db->mysqli); // mysqli object

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