retrieve wordpress post-meta using php not wordpress functions

Question

I am trying retrieve wordpress postmeta USING PHP not WORDPRESS functions, it needs to be in php no wordpress functions please.

this is what I have:

$resultat = mysqli_query($con,"SELECT * FROM wp_posts 
                                 LEFT JOIN wp_postmeta 
                                 ON wp_posts.ID= wp_postmeta.post_id 
                                 where post_type='shop_order'");

the issue here is each meta key is in its own row so this doesn't work :/ any suggestions please?

what I figured could be done is to get all the post ids first , store then in array then retrieve the values of each? let me know what you think

Answer 1

The reverse mechanism should work. I assume you are trying the get post metadata with the post row.

$resultat = mysqli_query($con,"SELECT * FROM wp_postmeta 
                                 LEFT JOIN wp_post 
                                 ON wp_postmeta.post_id = wp_post.ID 
                                 WHERE wp_post.post_type='shop_order'");

However, there will be a lots of duplication. If one post have 100 metadata, you are also getting the post row 100 times.