Du bör helt enkelt skapa ett uttalande så här:
$query = 'SELECT COUNT(*) AS total FROM articles WHERE MATCH(title) AGAINST (:query IN BOOLEAN MODE)';
$stmt = $pdo->prepare($query);
Och bind sedan parametrarna:
$keywords = ['php', 'mysql'];
$against = '';
for($i = 0; $i < count($keywords); $i++){
$against .= ' +' . $keywords[$i];
}
$stmt->execute(array(
':query' => $against
));