//多表联查,按字段,
public function test()
{
$list = Db::name('tp_product')
->alias('a')
->join('tp_pr_meb b','a.id=b.prid')
->join('tp_member c','c.id=b.mid')
->field('a.id,a.product_name,a.product_img,c.id,c.name,c.company')
->order('sort','desc')
->select();
dump($list);
}
