yast and zypper both freeze when trying to install software

I am testing a box with opensuse 13.1 64 bit. The install went well and I installed some software via yast. I closed yast, then decided to reopen yast and found that after loading the repositories, it would just hang. A reboot did not fix it and I would have to use 'kill pid xxx' to close the yast software installer. Every other yast module works. Then I tried zypper and had the same problem. Zypper stopped at 'reading installed packages...'

I tried 'rpmdb --rebuilddb'

I have used 13.1 since it came out and never had this problem. Does it sound like a corrupt data base and how can I trouble shoot it?