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 FROM language ORDER BY base DESC"
);
$langs = $result->fetchAll(PDO::FETCH_COLUMN);
var_export($langs);
$langs = $result->fetchAll(PDO::FETCH_ASSOC);
var_export($langs);
$langs = array_combine($result->fetchAll(PDO::FETCH_COLUMN), $result->fetchAll(PDO::FETCH_ASSOC));
var_export($langs);