Home  >  Article  >  Backend Development  >  Summary of common functions for CI framework AR database operations_php example

Summary of common functions for CI framework AR database operations_php example

WBOY
WBOYOriginal
2016-12-05 13:28:291342browse

The examples in this article describe common functions for CI framework AR database operations. Share it with everyone for your reference, the details are as follows:

1. Query table records

$this->db->select();  //选择查询的字段
$this->db->select_max();
$this->db->select_min();
$this->db->select_avg();
$this->db->select_sum();
$this->db->from();   //选择表名
$this->db->join();
$this->db->get();   //得到查询结果
$this->db->get_where();
$this->db->where();
$this->db->or_where();
$this->db->where_in();
$this->db->or_where_in();
$this->db->where_not_in();
$this->db->or_where_not_in();
$this->db->like();
$this->db->or_like();
$this->db->not_like();
$this->db->or_not_like();
$this->db->group_by();
$this->db->distinct();
$this->db->having();
$this->db->or_having();
$this->db->order_by();
$this->db->limit();
$this->db->count_all_results();

2. Add table records

$this->db->insert();

3. Change table records

$this->db->set();
$this->db->update();

4. Delete table records

$this->db->delete();

5. Clear table records

$this->db->empty_table();
$this->db->truncate();

6. Cache part

$this->db->start_cache()
$this->db->stop_cache()
$this->db->flush_cache()

7. Result set

result()  //返回对象数组
result_array() //返回二维数组
row()   //返回一个对象
row_array()  //返回一维数组
num_rows()  //返回查询的行数
num_fields() //返回查询结果的字段数
free_result() //释放查询所占的资源内存

8. Auxiliary query function

$this->db->insert_id()  //获取刚刚插入的id
$this->db->affected_rows() //修改或插入影响的行数
$this->db->count_all();  //统计记录的总条数 这一函数加入where条件无效
$this->db->last_query();  //最后一条执行的sql语句
//注意以下两个函数仅返回sql语句 不执行sql语句
$data = array('name' => $name, 'email' => $email, 'url' => $url);
$str = $this->db->insert_string('table_name', $data);
$data = array('name' => $name, 'email' => $email, 'url' => $url);
$where = "author_id = 1 AND status = 'active'";
$str = $this->db->update_string('table_name', $data, $where); //返回正确格式的更新字符串

PS: For detailed usage tips of CodeIgniter, please refer to this site’s online manual:

CodeIgniter 2.2.4 User Guide:
http://shouce.php.net/codeigniter2.2/

CodeIgniter 3.0 User Guide:
http://shouce.php.net/codeigniter3.0/

Readers who are interested in more CodeIgniter related content can check out the special topics of this site: "codeigniter introductory tutorial", "CI (CodeIgniter) framework advanced tutorial", "php excellent development framework summary", "ThinkPHP introductory tutorial", "ThinkPHP Summary of common methods", "Zend FrameWork framework introductory tutorial", "php object-oriented programming introductory tutorial", "php+mysql database operation introductory tutorial" and "php common database operation skills summary"

I hope this article will be helpful to everyone’s PHP program design based on the CodeIgniter framework.

Statement:
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn