我想要受影响的行数据和受 codeigniter 中的更新查询影响的列

Question

Is there a way to obtain only the affected columns after an update query? After an update query, that involves 10 columns, I know that only 2 columns are really updated (because the values of the other cols don't change). I need to know the names of the changed cols, for logging purpose.

$this->db->query("UPDATE `table1` SET name = $name,......................,column10=10 WHERE id=$id")->result();
$this->db->affected_rows();

This code gives number of affected rows but i want the data and updated column information.

Answer 1

As far as I know there are no built-in CodeIgniter functionality for that. You could compare old value with new value though :

$last_record = $this->db->get_where('table1', array('id' => $id))->row_array();
$this->db->query("UPDATE `table1` SET name = $name,......................,column10=10 WHERE id=$id")->result();
// $this->db->affected_rows();
$new_record = $this->db->get_where('table1', array('id' => $id))->row_array();
$affected_columns = array_diff($new_record, $last_record);
foreach ($affected_columns as $field => $value) {
    echo "[field] : $field\r\n";
    echo "[old_value] : $last_record[$field]\r\n";
    echo "[new_value] : $value\r\n";
    echo "\r\n";
}

This will print each of the of the updated column with it's old-new value respectively.