列举Django ORM中2种能写SQL语句的方法

靠近原生SQL --> extra()、raw()
- extra
def extra(self, select=None, where=None, params=None, tables=None, order_by=None, select_params=None)
    # 构造额外的查询条件或者映射，如：子查询
    Entry.objects.extra(select={'new_id': "select col from sometable where othercol > %s"}, select_params=(10,))
    Entry.objects.extra(where=['headline=%s'], params=['Lennon'])
    Entry.objects.extra(where=["foo='a' OR bar = 'a'", "baz = 'a'"])
    Entry.objects.extra(select={'new_id': "select id from tb where id > %s"}, select_params=(10,), order_by=['-nid'])

- raw 
def raw(self, raw_query, params=None, translations=None, using=None):
    # 执行原生SQL
    models.UserInfo.objects.raw('select * from userinfo')
    # 如果SQL是其他表时，必须将名字设置为当前UserInfo对象的主键列名
    models.UserInfo.objects.raw('select id as nid,name as title  from 表')
    # 为原生SQL设置参数
    models.UserInfo.objects.raw('select id as nid from userinfo where nid>%s', params=[12,])
    # 将获取的到列名转换为指定列名
    name_map = {'first': 'first_name', 'last': 'last_name', 'bd': 'birth_date', 'pk': 'id'}
    Person.objects.raw('SELECT * FROM some_other_table', translations=name_map)
    # 指定数据库
    models.UserInfo.objects.raw('select * from userinfo', using="default")