Error: rpmdb open failed

YUM Error :  rpmdb open failed

To remove this error, Run these commands.

First clean up downloaded yum cache.

# yum clean all

Now remove all db files

# rm -f /var/lib/rpm/__db*

Rebuld the rpm database

# rpm --rebuilddb

Update yum

# yum update

OR
Method - II

# rm -f /var/lib/rpm/__db.[0-9][0-9]*
# rpm --quiet -qa

If you get the error
rpmdb: write: 0xvendor-id, product-id: No space left on device
after running above commands. Check space in your filesystem.