联合查询
1、原生查询
$sql =$sql='select p.product_name,z.message as zmessage,z.rdtime,r.message,r.rdtime from wsd_product as p,wsd_product_zixun as z,wsd_product_zixun_reply as r where p.id=z.lipin_id and z.id=r.zixun_id order by z.rdtime';
$list = $Form->query($sql);
2、join() 两表查询
$list = $Form->join('think_sort ON think_form.sort_id = think_sort.sort_id' )->select();
3、join() 多表查询
$list = $Form->join('think_sort ON think_form.sort_id = think_sort.sort_id' )->join('think_brand ON think_form.brand_id = think_brand.brand_id' )->select();
4、table()
$list = $user->table('user_status stats, user_profile profile')->where('stats.id = profile.typeid')->field('stats.id as id, stats.display as display, profile.title as title,profile.content as content')->order('stats.id desc' )->select();