Summary of codeigniter database operation functions_PHP tutorial

There are many introductions to Codeigniter database operations on the Internet. Here is a summary.

Copy code The code is as follows:

//Query:
$query = $this->db_query("SELECT * FROM table");
==================================

//result () Return object array
$data = $query->result();

//result_array() Return data
$data = $query->result_array();

//row() only returns one row of object array
$data = $query->row();

//num_rows() returns the number of query result rows
$data = $query->num_rows();

//num_fields() returns the number of fields requested by the query
$data = $query->num_fields();

/ /row_array() returns only one row array
$data = $query->row_array();

//free_result() releases the memory occupied by the current query and deletes the associated resource identifier
$ data = $query->free_result();

/*
============================ ======
Insert operation
====================================
*/

//ID generated by the last insert operation
echo $this->db->insert_id();

//Write and update operations are affected The number of rows
echo $this->db->affected_rows();

//Returns the total number of rows in the specified table
echo $this->db->count_all(' table_name');

//Output the current database version number
echo $this->db->version();

//Output the current database platform
echo $this->db->platform();

//Return the last query statement run
echo $this->db->last_query();

//Insert data, the inserted data will be automatically converted and filtered, for example:
//$data = array('name' => $name, 'email' => $email, 'url ' => $url);
$this->db->insert_string('table_name', $data);

/*
======== =========================
Update operation
================= =================
*/

//Update data, the updated data will be automatically converted and filtered, for example:
/ /$data = array('name' => $name, 'email' => $email, 'url' => $url);
//$where = "author_id = 1 AND status = ' active'";
$this->db->update_string('table_name', $data, $where);

/*
========== ========================
Select data
================== ================
*/

//Get all data of the table
$this->db->get('table_name ');

//The second parameter is the number of output items, and the third parameter is the starting position
$this->db->get('table_name', 10, 20);

//Get data, the first parameter is the table name, the second parameter is the acquisition condition, and the third parameter is the number of items
$this->db->get_where('table_name', array('id'=>$id), $offset);

//Select method to obtain data
$this->db->select('title, content, date') ;
$data = $this->db->get('table_name');

//Get the maximum value of the field. The second parameter is an alias, which is equivalent to max(age) AS nianling
$this->db->select_max('age');
$this->db->select_max('age', 'nianling');

//Get the minimum value of the field
$this->db->select_min('age');
$this->db->select_min('age', 'nianling');

//Get the sum of fields
$this->db->select_sum('age');
$this->db->select_sum('age', 'nianling ');

//Customized from table
$this->db->select('title', content, date');
$this->db-> ;from('table_name');

//Query condition WHERE name = 'Joe' AND title = "boss" AND status = 'active'
$this->db->where( 'name', $name);
$this->db->where('title', $title);
$this->db->where('status', $status );

//Range query
$this->db->where_in('item1', 'item2');
$this->db->where_not_in(' item1', 'item2');

//Matching, the third parameter is the matching mode title LIKE '%match%'
$this->db->like('title', 'match', 'before/after/both');

http://www.bkjia.com/PHPjc/788620.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/788620.htmlTechArticleThere are many introductions to Codeigniter database operations on the Internet. Here is a summary. Copy the code as follows: //Query: $query = $this-db_query("SELECT * FROM table"); ===========...