I'm currently developing a Wordpress website that has a large navigation that lists the 4 most recent posts within a hierarchical taxonomy. I dont have any experience with $wpdb, but it seems like that would be the most efficient way to get results for many taxonomies as opposed using many WP_Query s for each tax... this site also gets a considerable amount of traffic. I am using transients API and caching other things well...
So basically to reiterate, I'm trying to do this:
1) I have 22 terms within a custom taxonomy.
2) I need to select the 4 most recent posts within each term
3) I need the title, the post thumbnail, and the permalink
4) These are all going to be either posts or pages
Any tips or help is hiiiighly appreciated.