I've run the google-pagespeed-insight tool, on which one link has been marked as not being https. Further investigations lead to a lot of links in wp_posts having http://localhost/(...) as links.
It may be due to me moving of the site from a localhost installation to the live webspace.
So I'm wondering, if i could delete those links, as they won't really point anywhere. Is there anything else i'd have to check, like other tables?
Thanks folks!
Investigated links via wp_posts and found lots of localhost ones.
If the URL's are not being triggered on the pages then you are free to delete them, however this could result in unwanted errors. Therefor I suggest you replace all old localhost URL's inside of your database with your new URL.
You can achieve this using the following SQL query.
UPDATE wp_options SET option_value = replace(option_value, 'oldurl.com', 'newurl.com') WHERE option_name = 'home' OR option_name = 'siteurl';
UPDATE wp_posts SET guid = replace(guid, 'oldurl.com','newurl.com');
UPDATE wp_posts SET post_content = replace(post_content, 'oldurl.com', 'newurl.com');
UPDATE wp_postmeta SET meta_value = replace(meta_value,'oldurl.com','newurl.com');
Or you can use a WordPress plugin, when I worked with WordPress we mostly used wp-all-import. Make sure that after you imported a website using any migration plugin you save the permalinks in the settings tab in wp-admin.