Sounds like there is not enough space on the partition you are hosted on.
GrandMaster Reviewed by GrandMaster on . What does this database error mean. I got this in my email about 4 of them mailed to me from my website: Database error in vBulletin 3.8.4: Invalid SQL: SHOW COLUMNS FROM user LIKE 'username'; MySQL Error : Can't create/write to file '/tmp/#sql_7a78_0.MYI' (Errcode: 28) Error Number : 1 Request Date : Friday, September 25th 2009 @ 03:32:35 PM Rating: 5