Custom column in wp_posts

I wasn’t able to find a direct answer to this.

Is it safe to add a custom column to wp_posts rather than JOINING with wp_postmeta? Having to “pivot” the meta_key/meta_value for several custom fields in wp_postmeta is becoming rather unwieldy.

I’m using a custom post type with many custom fields currently stored in wp_postmeta. My query is huge because of this – 12 joins for 12 custom fields in order to “pivot” them into typical columns for the queried results. I’d rather just add these fields as custom columns to wp_posts, which I believe would dramatically simplify the query.