I got an sql error when i was deactivating my survey.
It's a fresh installation and i didn't create any surveys but just imported one. So at deactivationg following page is shown:

"Internal Server Error
CDbCommand failed to execute the SQL statement: SQLSTATE[42P01]: Undefined table: 7 ERROR: relation "_tid_seq" does not exist

An internal error occurred while the Web server was processing your request. Please contact the webmaster to report this problem.

Thank you."

Here is the sql log file entry:
"2014-10-16 11:39:42 CEST ERROR: relation "_tid_seq" does not exist
2014-10-16 11:39:42 CEST STATEMENT: ALTER TABLE "_tid_seq" RENAME TO "_tid_seq""

i guess it's produced by the following line 331: application/controllers/admin/surveyadmin.php line 326:
"
//See if there is a tokens table for this survey
if (tableExists("{{tokens_{$iSurveyID}}}"))
{
if (Yii::app()->db->getDriverName() == 'pgsql')
{
$deactivateresult = Yii::app()->db->createCommand()->renameTable($toldtable . '_tid_seq', $tnewtable . '_tid_seq');
$setsequence = "ALTER TABLE ".Yii::app()->db->quoteTableName($tnewtable)." ALTER COLUMN tid SET DEFAULT nextval('{{{$tnewtable}}}_tid_seq'::regclass);";
$deactivateresult = Yii::app()->db->createCommand($setsequence)->query();
$setidx = "ALTER INDEX {{{$toldtable}}}_idx RENAME TO {{{$tnewtable}}}_idx;";
$deactivateresult = Yii::app()->db->createCommand($setidx)->query();
}
"

Finally this relation definitly doesn't exist. The only table with "t" is templates. I looked through the rest of my log file but the installation didn't show any errors.