abstract_adapter.rb:150:in log': Mysql::Error: Can't create/write to file 'C:\MySQL5\tmp\#sql_190_0.MYI' (Errcode: 13)
I had been getting this issue quite a bit recently. The cause actually turned out to be a conflict between McAfee and MySQL. What was happening is that McAfee scans any file that is recently written to, especially those in tmp directories. McAfee reading the file causes the above issue to MySQL. The fix is 2 fold. First, if you have not already, move the location of the MySQL tmp file. You can do this by editing my.ini in your MySQL directory. For Example:
You may also have to add an exception to your antivirus so that it will no longer scan this file. I had to do this because I was using corporate antivirus. You may have to get your Sysadmin to do this.