MySQL - Is a query with many results or several queries with one result more efficient? [duplicate]

Question

I need to get category titles for which I am using the a model where $result returns all the data from the categories table, what I need is only the titles, that by making a loop to $result and a comparison with in_array() I can obtain them.

$cat_ids = $params->get('catid'); // this is = array(2, 3, 4, 5, 7);
$categories = JModelLegacy::getInstance('Categories', 'ContentModel',array('ignore_request' => true));
$categories_items = $categories->getItems();
$category_titles = array();
foreach ($categories_items as $category) {
    if (in_array($category->id, $cat_ids)) {
        $category_titles[] = $category->title;
    }
}
return $category_titles;

These titles can also be obtained by making a loop of $catids and in each iteration call to the database with $db = JFactory::getDbo();in this case if I need 5 titles I must make 5 queries to the database data.

$category_titles = array();
foreach ($cat_ids as $id) {
    $db = JFactory::getDbo();
    $query = $db->getQuery(true);
    $query->select('title');
    $query->from($db->quoteName('#__categories'));
    $query->where($db->quoteName('id') . ' = ' . $db->quote($id));
    $db->setQuery($query);
    $category_titles[] = $db->loadResult();
}
return $category_titles;

My question: which is more efficient? do a query with lots of data or lots of queries with unique data?

Thanks. (I'm sorry for my English)