Get all custom_post_type posts + blog posts from one category in a single query

Question

Is there a way to query posts from multiple post_type's and filter the normal blog posts by a category?

I am trying to display the 10 latest custom_post_type posts and blog posts on my homepage in a single query - so that I have 10 posts in total, sorted by post_date in DESC order, containing all posts from my custom_post_type and blog posts from a certain category.

Let's say I have custom post type called news. I want to query both news and posts, but limit posts to category with id 3. I do NOT want to limit news to any category.

$args = array (
    'cat' => 3,
    'post_type' => array ( 'news', 'post' )
);

The above code seems to only work half - it only fecthes blog posts from the category 3, but no custom_post_types at all...

Answer 1

That should work. Make sure there're no typos in your custom post type name or where you register the post type.

If that fails try using:

'post_type' => 'any'

Answer 2

WordPress query logic is aimed at retrieving single set of posts, satisfying all the query conditions. What you want is combination of two different sets of posts.

One of the way to accomplish that would be querying for IDs of posts ( 'fields' => 'ids' ) in each set and then combine them to use as post__in argument for final query.

To do this in one query precisely will require modifying raw underlying SQL and is much less convenient.