In some rare cases Magento doesn't add tables on installation, but it creates an entry in core_resource. This produces error
Base table or view not found...
If I delete core_resource entry it will go through sql install script again and this time it will add also tables and everything starts working again. I can not figure out when this happens, it happens just in some cases, sometimes if my customer uses FTP upload and sometimes if he/she install it through Magento Connect Manager.
I am wondering when exactly Magento adds core_resource entry. I thought it adds it once it completes sql installer script. But if this was true, then it would add sql tables OR it wouldn't add sql tables and it also wouldn't add core_resource entry.