Choose permalink on a per-post basis?

I’ve fixed this. Some sort of bug was hiding it. Apparently all i had to do was checking “Post name” option under Settings > Permalinks as explained on http://www.wpbeginner.com/wp-tutorials/how-to-fix-wordpress-posts-returning-404-error/

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)