Codeigniter active record update statement with a join

Question

This is the query that i'm trying to achieve via active record:

UPDATE `Customer_donations` cd 
join Invoices i on i.cd_id = cd.cd_id 
set cd.amount = '4', cd.amount_verified = '1' 
WHERE i.invoice_id =  '13';

This is my attempt at the active record:

$data = array('cd.amount'=>$amount, 'cd.amount_verified'=>'1');
$this->db->join('Invoices i', 'i.cd_id = cd.cd_id')
     ->where('i.invoice_id', $invoiceId);


// update the table with the new data
if($this->db->update('Customer_donations cd', $data)) {
  return true;
}

And this is the query that's actually getting produced:

UPDATE `Customer_donations` cd 
SET `cd`.`amount` = '1', `cd`.`amount_verified` = '1' 
WHERE `i`.`invoice_id` =  '13'

Why is this active record statement not applying my join clause?

Answer 1

How about the solution below? A bit ugly but it achieved what you expected in your question.

$invoiceId = 13;
$amount = 4;
$data = array('cd.amount'=>$amount, 'cd.amount_verified'=>'1');

$this->db->where('i.invoice_id', $invoiceId);

$this->db->update('Customer_donations cd join Invoices i on i.cd_id = cd.cd_id', $data);