If you've recently upgraded to Habari 0.6, you've probably discovered that the Habari Backup plugin doesn't work. Your log will show you an entry complaining about a table not existing:
PDOStatement::execute() [function.PDOStatement-execute]: SQLSTATE[42S02]: Base table or view not found: 1146 Table 'habari.habari__permissions' doesn't exist in system/classes/databaseconnection.php:289
This is due to some left-over code hanging around in the core Habari source. The databaseconnection.php class has an array manually declaring all the tables used in Habari. At one point, there was a "permissions" table, but it was excised some time ago. We forgot to remove it from that array, so when the Habari Backup plugin asks for a list of all the tables, it gets a response that includes a table that doesn't exist. It happily tries to backup that table, and MySQL barfs on you. Hooray!...
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