How to use the “meta_key” …

Hello，
Here is my code.

[su_posts template=”templates/loop-featured-news.php” posts_per_page=”3″ post_type=”post” taxonomy=”category” tax_term=”26″ meta_key=”left” order=”DESC” orderby=”date”]

I created a custom field named “home_left” in order to add a filter for post list, I hope to get the post list which the value is “left” for “home_left”, Please let me know how to edit the code.

Waiting for the reply.

Thanks a lot.

Bruce