CREATE TABLE language (
code varchar(3), title varchar(64), base int, id int
);
INSERT INTO language VALUES ('ru', 'Russian', 0, 1), ('en', 'English', 0, 2);
<?php
$result = $pdo->query(
"SELECT code, title, base, id FROM language ORDER BY base DESC"
);
$langs = $result->fetchAll();
$langs = array_combine(array_column($langs, 'code'), $langs);
var_export($langs);