Can I save part of the post in an external file and join it on the fly to avoid redundancy in the wp_posts table?

Can I save part of the post in an external file and join it on the fly to avoid redundancy in the wp_posts table?

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