如何判断mysql数据库中的链接是否有效？

Question

Massive Novice, so any help greatly appreciated.

I have a mysql database with about 30,000 entries, each with a link to a thumbnails in .jpg format.

I was trying to figure out if there was anyway to go through the mysql database and verify that each link is still valid - aka if the .jpg file is where it is meant to be?

So each entry has an id, name, thumb (which is an url).

Thanks!

Answer 1

For links, do a query to get all the links, something like:

SELECT DISTINCT url FROM your_stuff;

You didn't mention the exact nature of your database, but something like that should work.

Then loop over it and for each one, use something like cURL to do a HEAD request - this is better than a usual GET request because it's identical, except the server shouldn't return the actual file, so you don't have to download every image just to see if they're there. Just do the HEAD request, and confirm that the server answered with a status 200.

This question goes into a little more about the HEAD request in cURL.