Zend_Db_Table_Select_Exception example

            $from = $this->getPart(Zend_Db_Table_Select::FROM);

            if ($this->_integrityCheck !== false) {
                foreach ($fields as $columnEntry) {
                    list($table, $column) = $columnEntry;

                    // Check each column to ensure it only references the primary table                     if ($column) {
                        if (!isset($from[$table]) || $from[$table]['tableName'] != $primary) {
                            throw new Zend_Db_Table_Select_Exception('Select query cannot join with another table');
                        }
                    }
                }
            }
        }

        return parent::assemble();
    }
}