Error: Call to undefined function SUM()

Question

使用 cakephp 2

$total = $this->order->find('all', array(
    'fields'     => array(SUM(order.vat)),
    'conditions' => $condition
));

SUM 函数对我不起作用，出现错误：

Call to undefined function SUM()

Answer 1

你要这么写，

$total = $this->order->find('all',array(
  'fields'=>array('SUM(order.vat) as total_vat'),
  'conditions'=>$condition
));

在 SUM(order.vat) 周围添加引号。

Answer 2

这是另一个解决方案。

$this->order->virtualFields['total_vat']='SUM(order.vat)';

$total = $this->order->find('all',array(
  'fields'=>array('total_vat'),
  'conditions'=>$condition
));