Every few weeks, i receive the message
The table 'ttrss_users' is full from an installation of http://tt-rss.org/redmine/ (a RSS reader application written in PHP).
It's always the users table (InnoDB), which has the following layout:
id int(11) login varchar(120) pwd_hash varchar(250) last_login datetime access_level int(11) theme_id int(11) email varchar(250) full_name varchar(250) email_digest tinyint(1) last_digest_sent datetime created datetime twitter_oauth longtext
The query causing the error is:
UPDATE ttrss_users SET last_login = NOW() WHERE id = x and affects only this table (no other table or database on this server).
The only solution i found is to restart the server. Changing
AVG_ROW_LENGTH via ALTER TABLE seems to affect MyISAM tables only.