Select ID 不在另一个 table 中的所有记录使用 Cakephp 2.x

Question

你好我想在我的查询中实现 OR 条件，它将从另一个 table 中获取所有记录，其中 id 不存在 OR 获取已插入的记录最后 24 小时。

此查询正在获取过去 24 小时的结果

        $this->Behaviors->attach('Containable');
        return $this->find('all', array(

            'contain' => array(
              'User','UserInfo','QuestionAndTopic.Topic','UpVoteQuestion','Answer'

            ),
             'conditions' => array(
                'Question.created >=' => date('Y-m-d H:i:s', strtotime('-24 hour'))

            ),

            'order' => 'Question.question_id DESC',
            'recursive' => 0
        ));

我想做这样的事情

$this->Behaviors->attach('Containable');
return $this->find('all', array(

    'contain' => array(
      'User','UserInfo','QuestionAndTopic.Topic','UpVoteQuestion','Answer'

    ),
     'conditions' => array(
         'OR' => array(
    array( 'Question.created >=' => date('Y-m-d H:i:s', strtotime('-24 hour'))),
    array('Question.question_id NOT IN ' => 'Answers'),// get results where question id is not present in answers table as foreign key
)



    ),

    'order' => 'Question.question_id DESC',
    'recursive' => 0
));

希望你能理解我的问题

Answer 1

有几种方法可以做到这一点。

1) 您可以使用左连接并检查没有答案的地方。

在SQL中：

select * 
from questions 
left join answers on questions.id = answers.question_id
where answers.id is null;

在 CakePHP 中：

$this->find('all', array(
    'contain' => array(
        'User','UserInfo','QuestionAndTopic.Topic','UpVoteQuestion','Answer'
    ),
   'conditions' => array(
       'OR' => array(
           array( 'Question.created >=' => date('Y-m-d H:i:s', strtotime('-24 hour'))),
           array('Answer.id is null'),// get results where question id is not present in answers table as foreign key
       )
    ),
    'order' => 'Question.question_id DESC',
    'recursive' => 0
));

2)

您可以使用子查询加载答案中的问题 ID 列表 table，并使用基本 not in 获取补充集。

在SQL中：

select * from questions where id not in (select distinct question_id from answers);

在 CakePHP 中：

cakephp 中的子查询有点复杂。您首先必须设置子查询，然后在查询中调用它。参见 https://book.cakephp.org/2.0/en/models/retrieving-your-data.html#sub-queries

我从未尝试在条件中使用子查询，但我认为这应该可行。

$db = $this->getDataSource();
$subquery = $db->buildStatement(
    array(
        'table' => 'answers',
        'alias' => 'Answer',
        'fields' => 'question_id'
    ),
    $this
);
$this->find('all', array(
    'contain' => array(
        'User','UserInfo','QuestionAndTopic.Topic','UpVoteQuestion','Answer'
    ),
   'conditions' => array(
       'OR' => array(
           array( 'Question.created >=' => date('Y-m-d H:i:s', strtotime('-24 hour'))),
           array('Question.question_id NOT IN ' => '($subquery)'),// get results where question id is not present in answers table as foreign key
       )
    ),
    'order' => 'Question.question_id DESC',
    'recursive' => 0
));

Select ID 不在另一个 table 中的所有记录使用 Cakephp 2.x

Select all records where the id is not in another table using Cakephp 2.x

php

mysql

cakephp

cakephp-2.0