what is the correct way to process database? - php

Question

The code below only deletes the data when I add the extra statement in the controller. why is that?
I've only been using codeigniter for a few months now and I keep getting stuck with weird bugs like this.
this is the models file:
My_model.php
function delete_data($where=array())
{
return $this->db->delete('table1', $where);
}
and the code in controller:
tasks.php
function do_delete_data()
{
$this->load->model('My_model');
$result = array('status' => '', 'message' => '');
try
{
$this->db->trans_begin();
$id = $this->input->post('post_id', TRUE);
if ( ! $this->My_model->delete_data(array('id' => $id)))
{
throw new Exception('Database process failed.');
}
$result['message'] = $this->db->last_query(); // extra statement
$this->db->trans_commit();
$result['status'] = 1;
}
catch(Exception $e)
{
$this->db->trans_rollback();
$result['message'] = $e->getMessage();
}
if ($this->input->is_ajax_request())
{
echo json_encode($result);
}
}
it works fine until recently I tried to call this function via ajax like this:
display.php
$.ajax({
url: '/tasks/do_delete_data',
type: 'post',
data: {
'post_id' : $('#post_id').val(), // e.g. 12
},
dataType: 'json',
success: function(response) {
alert('File deleted successfully.');
console.log(response);
},
error: function(e) {
alert('an error occurred.');
}
});

Answer 1

You are using id in ajax param but using post_id as in your controller, which is undefined index.
You need to correct your index name as:
$id = $this->input->post('id', TRUE); // use id
It's better to check what are you getting in controller by using print_r($_POST) this will you to understand, what kind of array are you getting from ajax data.