CodeIgniter single update query to update one column with an existing columns data?

问题

In my db I have a Last and a Current column for datetime. Just to keep an eye on when someone last used a valid login to the service I am building up.

What I want to know is, is it possible to update one column on a row with another column from that row, while updating the other column at the same time

Ie: Set the Last as the current Current, then set the Current with the date thats right now essentially?

Make any sense?

回答1:

Try like this ..

$data=array('current_login'=>date('Y-m-d H:i:s'));
$this->db->set('last_login','current_login',false);
$this->db->where('id','some_id');
$this->db->update('login_table',$data);

query generated by above code :--

UPDATE login_table SET last_login = current_login, current_login = '2018-01-18 15:24:13' WHERE id = 'some_id'

回答2:

$data = array( 
    'name'      => $_POST['name'] , 
    'groupname' => $_POST['groupname'], 
    'age'       => $_POST['age']
);

$this->db->where('id', $_POST['id']);

$this->db->update('tbl_user', $data);

回答3:

if you want to upgrade only a single column of a table row then you can use as following:

$this->db->set('column_header', $value); //value that used to update column  
$this->db->where('column_id', $column_id_value); //which row want to upgrade  
$this->db->update('table_name');  //table name

回答4:

$this->db->set('usage', 'usage');  //Set the column name and which value to set..

$this->db->where('tag', 'java'); //set column_name and value in which row need to update

$this->db->update('tags'); //Set your table name

Try this...

回答5:

        $id= $this->input->Post('edit_id');
        $date= $this->input->Post('date');
        $title=$this->input->Post('title');
        $content=$this->input->Post('content'); 

 $value=array('date'=>$date,'content'=>$content,'title'=>$title);
 $this->db->where('course_id',$id);
 if( $this->db->update('course',$value))
      {
        return true;
      }
      else
      {
        return false;
      }

回答6:

I use this function for all updates in my CI sites

function _updateRowWhere($table, $where = array(), $data = array()) {
    $this->db->where($where);
    $this->db->update($table, $data);
}

回答7:

Alternative Short-hand way to write update query is like below...

$this->db->update('student',array('class'=>'xyz','name'=>'abc'),array('stud_id'=>20);

set class xyz, name abc where stud_id=20 in "student" table..

回答8:

Try the below code:

$data = array(
    'name' = > $_POST['name'] ,
    'groupname'= > $_POST['groupname'],
    'age' = > $_POST['age']
);
$this->db->where('id', $_POST['id']);
$this->db->update('tabname', $data);

来源：https://stackoverflow.com/questions/18691972/codeigniter-single-update-query-to-update-one-column-with-an-existing-columns-da

标签

php

mysql

codeigniter

activerecord