I did try to upgrade q2a from 1.7.0 to 1.7.1
All I did was upload and overwrite the QA files, then visited my website and clicked upgrade database.
Question2Answer was unable to perform the installation query below. Please check the user in the config file has CREATE and ALTER permissions:
SHOW COLUMNS FROM qa_options
Error 1: Can't create/write to file '/tmp/#sql_9ba8_0.MYI' (Errcode: 28)