Omeka has encountered an error

Zend_Db_Statement_Mysqli_Exception

Mysqli prepare error: Expression #1 of ORDER BY clause is not in GROUP BY clause and contains nonaggregated column 'studento.et_sort.text' which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_full_group_by

#0 /var/www/studento/application/libraries/Zend/Db/Statement.php(115): Zend_Db_Statement_Mysqli->_prepare('SELECT `items`....')
#1 /var/www/studento/application/libraries/Zend/Db/Adapter/Mysqli.php(388): Zend_Db_Statement->__construct(Object(Zend_Db_Adapter_Mysqli), 'SELECT `items`....')
#2 /var/www/studento/application/libraries/Zend/Db/Adapter/Abstract.php(479): Zend_Db_Adapter_Mysqli->prepare('SELECT `items`....')
#3 /var/www/studento/application/libraries/Omeka/Db.php(79): Zend_Db_Adapter_Abstract->query('SELECT `items`....', Array)
#4 /var/www/studento/application/libraries/Omeka/Db/Table.php(590): Omeka_Db->__call('query', Array)
#5 /var/www/studento/application/libraries/Omeka/Db/Table.php(281): Omeka_Db_Table->fetchObjects(Object(Omeka_Db_Select))
#6 /var/www/studento/application/controllers/helpers/Db.php(59): Omeka_Db_Table->findBy(Array, 10, 1)
#7 /var/www/studento/application/libraries/Omeka/Controller/AbstractActionController.php(94): Omeka_Controller_Action_Helper_Db->__call('findBy', Array)
#8 /var/www/studento/application/controllers/ItemsController.php(184): Omeka_Controller_AbstractActionController->browseAction()
#9 /var/www/studento/application/libraries/Zend/Controller/Action.php(516): ItemsController->browseAction()
#10 /var/www/studento/application/libraries/Zend/Controller/Dispatcher/Standard.php(308): Zend_Controller_Action->dispatch('browseAction')
#11 /var/www/studento/application/libraries/Zend/Controller/Front.php(954): Zend_Controller_Dispatcher_Standard->dispatch(Object(Zend_Controller_Request_Http), Object(Zend_Controller_Response_Http))
#12 /var/www/studento/application/libraries/Zend/Application/Bootstrap/Bootstrap.php(97): Zend_Controller_Front->dispatch()
#13 /var/www/studento/application/libraries/Zend/Application.php(366): Zend_Application_Bootstrap_Bootstrap->run()
#14 /var/www/studento/application/libraries/Omeka/Application.php(79): Zend_Application->run()
#15 /var/www/studento/index.php(23): Omeka_Application->run()
#16 {main}