Wikimedia Bugzilla is closed!

(In reply to comment #0)
> When you move a page, the page_id changes. The new id doesn't show up in the
> log. While end users can see the old or new page name and namespace, this
> logging  makes it hard to programmatically hard to track page moves. 
> 
> I see two solutions here:
> 
> * Don't change the page_id when moving
> * Log the new and the old page_id when moving

Blergh. Should read: "makes it hard to programmatically track page moves."

I don't think the page ID changes, that would require an O(N) update of rev_page that does not exist AFAIK.

It doesn't change based on my local tests:

php> echo Title::newFromText('After move')->getArticleId();
320

php> echo Title::newFromText('After move')->getArticleId();
320

Same is confirmed using wgArticleId.  Can someone provide a way to reproduce this?  Otherwise, I will close as WORKSFORME.

I agree.  It seemed strange to me too.  I just realized that the logging table could be storing the page ID of the redirect that was created.  I'll try to demo the issue.

# Get the last page move in the logging table on enwiki:
> SELECT log_namespace, log_title, log_page, log_params FROM logging WHERE log_action = "move" and log_type = "move" AND log_namespace = 0 ORDER BY log_id DESC LIMIT 1;
+---------------+-----------+----------+------------------------------------------------------------------------+
| log_namespace | log_title | log_page | log_params                                                             |
+---------------+-----------+----------+------------------------------------------------------------------------+
|             0 | Chappo    | 41083072 | a:2:{s:9:"4::target";s:14:"Chappo (album)";s:10:"5::noredir";s:1:"0";} |
+---------------+-----------+----------+------------------------------------------------------------------------+
1 row in set (0.29 sec)


That means "Chappo" was moved to "Chappo (album)".  But the recorded page_id points to a new page that has become a redirect:

> select page_title, page_namespace from page where page_id = 41083072;
+------------+----------------+
| page_title | page_namespace |
+------------+----------------+
| Chappo     |              0 |
+------------+----------------+
1 row in set (0.04 sec)


If you view the content of the article at that page ID, you should see:
---------------------------------
#REDIRECT [[Chappo (album)]]
{{R from move}}
---------------------------------

My proposed solution is to store the page_id of the *moved page* in log_page and optionally store the page_id of the created redirect in the hashed array in log_params.  

This solution is slightly problematic since old code could be relying on the page_id of the redirect page appearing in log_page.  Though, I can't imagine why anyone would be looking for that there.

Sure enough.  log_page = 0 is no redirect is created. 

> SELECT log_id, log_namespace, log_title, log_page, log_params FROM logging WHERE log_action = "move" and log_type = "move" AND log_params LIKE '%"5::noredir";s:1:"1";%' ORDER BY log_id DESC LIMIT 1;
+----------+---------------+----------------------+----------+------------------------------------------------------------+
| log_id   | log_namespace | log_title            | log_page | log_params                                                 |
+----------+---------------+----------------------+----------+------------------------------------------------------------+
| 52627069 |             0 | UCI_(disambiguation) |        0 | a:2:{s:9:"4::target";s:3:"UCI";s:10:"5::noredir";s:1:"1";} |
+----------+---------------+----------------------+----------+------------------------------------------------------------+
1 row in set (0.04 sec)

Resolving per all the comments.

Yeah the old page ID makes sense to store, with the new one in params and possibly log_relations.

See bug 57084 for a new report covering the actual issue.