Not sure if it's a known bug but it looks like the zypper db can get a little screwy when adding some community repros. The problem could be something going wrong with zypper listings when the repros get refreshed and there are changes in the repro itself... I wouldn't now how to debug so call it a hunch. I've only had to 'repair' the db once or twice in a years time and seen a couple of others in the forum here.. but I don't think it's something that happens too often?

One option is to report this as a bug (or add to an existing report) and maybe ask an enhancement to let the zypper refresh run automated when these errors occur. The only downside I see in doing this is the time it takes to rebuild the db.
Though the first thing to do would be to find out what is exacly causing the problem.

Cheers,
Wj