Why majority of fileds in wp_posts table prefixed with post_?

You pretty much answered it – legacy code. WordPress is the result of years of code evolution, refactoring and (most importantly) multiple developers/coders/authors – whilst they’re getting pretty good at enforcing coding standards/consistency, there will always be a trail of the past.

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