Joomla Database Crash

I use Joomla on a couple of sites, and discovered one of them had crashed this morning with an error:

jtablesession::StoreFailed
DB function failed with error number 145
Table ‘.\joomla\jos_session’ is marked as crashed and should be repaired SQL=….

Googling, I found that the solution to this was to truncate the jos_session database table however I was unable to log onto the database using the mysql command line tool.

I found that restarting the database service and then truncating the table however did the track and everything is now back working.