Correct permissions for /var/www/html

apache-nginx-ftp

// Adding current user to www-data
sudo adduser $USER www-data

//change ownership to user:www-data and 
sudo chown $USER:www-data -R /var/www/html
sudo chmod u=rwX,g=srX,o=rX -R /var/www/html

// change file permissions of existing files and folders to 755/644
sudo find /var/www/html -type d -exec chmod g=rwxs "{}" \;
sudo find /var/www/html -type f -exec chmod g=rws "{}" \;

Remove all attachment wordpress

    # First:
     
    DELETE FROM wp_postmeta
    WHERE post_id IN
    (
    SELECT id
    FROM wp_posts
    WHERE post_type = 'attachment'
    )
    ;
     
    # Second:
     
    DELETE FROM wp_posts WHERE post_type = 'attachment'

DELETE relations., taxes., terms.*
FROM wp_term_relationships AS relations
INNER JOIN wp_term_taxonomy AS taxes
ON relations.term_taxonomy_id=taxes.term_taxonomy_id
INNER JOIN wp_terms AS terms
ON taxes.term_id=terms.term_id
WHERE object_id IN (SELECT ID FROM wp_posts WHERE post_type='product');

DELETE FROM wp_postmeta WHERE post_id IN (SELECT ID FROM wp_posts WHERE post_type = 'product');
DELETE FROM wp_posts WHERE post_type = 'product';