Getting warning message in statistics module
Doing this in phpMyAdmin solved my problem.


  
  Login to phpMyAdmin
  Choose the affected database. If you only have one database, it
  should choose it by default so you don't need to do anything.
  In the main panel, you should see a list of your database tables.
  Check the boxes by the tables that need repair.
  At the bottom of the window just below the list of tables, there is
  a drop down menu. Choose "Repair Table"
  


This should fix your table, and let you access it again. Now that it is fixed... it's a good idea to make that database backup!

taken from this source