Last modified: 2014-10-07 06:14:52 UTC
When you upload an image to Commons, you are not warned when your chosen filename is already used on a local wiki to host another file. Your upload will then show the 'wrong' image if you return to that local wiki. This is confusing behavior Possible solutions: 1: check 'uselang' and en.wp repo only for a clash 2: eradicated clashes alltogether and outlaw them 3: make hundreds of queries. Due to the many non-shared repositories being fed by Commons, this is probably very difficult to implement due to performance issues.
The only reasonable solution to this is keeping a global image table I think, and I'm not sure if that is desirable.
Forbid local uploads!
If checking all local wikis is not feasible, what about, for SUL accounts, checking just the user's home wiki? That's the most likely collision to cause immediate problems, certainly for Commons. On the other hand, now that Special:GlobalUsage exists, is it really too expensive to initiate a globalusage query on the proposed filename, and show the user the results if there are any hits?
Maybe the Extension GlobalUsage can give the information (Needs a hook in core, which than can be aborted by the Extension or so)
(In reply to comment #4) > Maybe the Extension GlobalUsage can give the information (Needs a hook in core, > which than can be aborted by the Extension or so) No, it can't, since it only tracks links to images that do not exist locally.