###Here's the TLDR: Is is possible to get all meta keys from a specific CPT without a database hit for each post? 

#If so, how can I do this the Wordpress way?  

This seems like a simple thing to do ( at least from a database perspective ) but I'm looking for the Wordpress way to get multiple post_meta values from a bunch of CPTs. Example:

Every `Product` Custom Post Type has the following fields ( plus many more ) which holds discrete pieces of information:

 - `_ns_research_document`
 - `_ns_monograph_document`
 - `_ns_profile_document`

Essentially, I want a list of ALL ***Research** Docs*, ***Monographs*** and ***Profile** Docs*. Currently this site has 72 `product` posts, but other sites this will be used on have over a thousand.

I assume there's a way to do this with wordpress methods that doesn't involve [at least] 73 calls ( one for all posts, and then `get_post_meta` inside the loop ). 

The general solution I've found suggest a get_post_meta inside a foreach loop: http://stackoverflow.com/questions/14699686/custom-post-type-loop-only-displays-first-post-meta-data

But in this case, I really only want the `meta_values` in an array for a specific **CPT**. 

Database Logic tells me that this should be only 2 queries... one on the post_meta table, one on the the posts table. It might include some joins, but still a rather inexpensive couple of queries.