Add featured photo and thumbnail using sql

Hi all,
I have a java app that generates sql code to insert posts directly to db,
now, i want to know how to add a featured image to post directly using sql, knowing that i have the post ID and the image file path. the image should be shown then as a thumbnail in home page, and as featured image in a magazine theme if the post is featured, and it should also show in the post when reading it.

Thanks.