How can i increment a field? PHP-CodePudding

How can i increment my qty every time i process i want it to increment the value not just update it?

$prodid = $this->input->post('product')[$x];
  if($prodid){
    $product_quanti = array(
        'qty' => $this->input->post('qty')[$x],
    );
        $this->db->where('id', $prodid);
        $update = $this->db->update('products', $product_quanti);

    }

i tried this

 $prodid = $this->input->post('product')[$x];
  if($prodid){
    $product_quanti = array(
        'qty' => $this->input->post('qty')[$x]   $this->input->post('qty')[$x],
    );
        $this->db->where('id', $prodid);
        $update = $this->db->update('products', $product_quanti);

    }

but every time i process it it just randomly increment a number i the qty was 200 and when i input 500 it randomly return 1000 how can i increment it in the correct way?

how can i make the avaiable stock incoming stock formula?

CodePudding user response：

You are setting the value to twice the input, instead of the current value the input. So 500 will result in 1000.

You can do something like this instead:

$inputQuantity = (int)$this->input->post('qty')[$x];
$this->db->where('id', $prodid);
$this->db->set('qty', "qty $inputQuantity", false);
$this->db->update('products');