Database corrupted getting the site crash I crashed my website trying to secure it by changing files and folders modifications...After i tried many things (chmod 777 -temporarly- all to take it back, clear the cache, drush rr...) nothing worked yet. So i tried to install a new site, copied all the site file...It was working perfectly. 

I tried to link the new site with my old database, and the fatal error get back again...I guess my database might be corrupted...Any idea ?

Thanks for your help

(previous conversation about what i did already here
As webdrips has said, your error seems to be with the xmlsitemap module, and considering it is not critical for functionality, you should try disabling it.

Depending on the state of the website, if you are experiencing WSOD, you may need to disable the module through the database using phpmyadmin. 

In the system table, find the xmlsitemap module, and edit the row where the column is "status", and set that to 0.