Duplicate ISBNs should not be allowed

[Graeme Pietersz]

It is currently possible to have two editions with the same ISBN 10 or ISBN 13.

This means that we either have a duplicate edition, or erroneous ISBNs. Either way an edit containing a duplicate ISBN should not be accepted.

[Jacob Gest (jakegest)]

I'm very unsure about other people that edit the database, but I spend a good amount of time correcting already existing records. This inevitably leads to me moving editions manually from one work to another (there is an enormous amount of duplicate works that need to be "merged" with their duplicates) To do this I have to create duplicate entries of editions and then ask an administrator to delete the old work and editions.... so this feature would make that much more difficult to do.

Just food for thought.

[Graeme Pietersz (fgpietersz)]

That would be a problem if duplicates were simply rejected.

If, instead, when you enter a duplicates ISBN you could be given the choice of:

1) correcting or removing what you just entered
2) correcting or removing the ISBN of the other edition
3) merging the works (or requesting that an admin does it)

Of course, this implies better support for merging works than what you describe, but should save work.

Allowing duplicate ISBNs has probably made the problem of duplicate works much worse by not drawing attention to it early.

[Tom Morris (tfmorris)]

One thing that needs to be taken into account that it is possible for two different books to end up with the same ISBN. The restriction on one book per ISBN can't be absolute in the software because it's not in the real world.