参数是否为FALSE的区别

 1 <?php
 2 //临时 获取科目
 3     function getLessonOfExams($where = FALSE) {
 4         $db = & $this->getAdapter();
 5         $select = $db->select();
 6         if ($where && is_array($where)) {
 7             foreach ($where as $key => $val) {
 8                 $select->where($key, $val);
 9             }
10         }
11         $select->from('t_exams as e', array('lesson_id'));
12         $select->joinLeft('lesson as l', 'e.lesson_id = l.id', 'l.name as name');
13         $select->group('e.lesson_id');
14         $result = $db->fetchAll($select);
15         return $result;
16     }
17 
18     //临时 获取大考
19     function getSequence($where) {
20         $db = & $this->getAdapter();
21         $select = $db->select();
22         $select->from('t_exams', array('sequence', 'sequence_name', 'type'));
23         if ($where && is_array($where)) {
24             foreach ($where as $key => $val) {
25                 $select->where($key, $val);
26             }
27         }
28         $select->group('sequence');
29         $result = $db->fetchAll($select);
30         return $result;
31     }