orm返回的数据有两种，QuerySet，object
1.QuerySet支持链式编程，可以在all()后面继续.方法
teachers = models.Teacher.objects.all() tea_name = teachers.values('name')#过滤字段，获取我们希望获取的字段 count = teachers.count()#获取qs的个数 firstData = teachers.first()#获取qs的第一个数据 value_name = teachers.values_list('name')#只返回要求过滤的字段的value值不返回key
2.object
teacher = models.Teacher.objects.get(id=1)
teachername = teacher.name
3.orm过滤 filter
teacher = models.Teacher.objects.filter(name__contains='大')#过滤 模糊查询 teacher = models.Teacher.objects.filter(name__endswith="牛")#以什么结尾 teacher = models.Teacher.objects.filter(name__startswith="大")#以什么开头 teacher = models.Teacher.objects.filter(name__in=['花开富贵','魏无羡'])#过滤 在什么范围内 teacher = models.Teacher.objects.filter(name__isnull=True)#过滤 为空 teacher = models.Teacher.objects.filter(id__gt=1)#过滤 大于 teacher = models.Teacher.objects.filter(id__gte=1)#过滤 大于等于 teacher = models.Teacher.objects.filter(id__lt=1)#过滤 小于 teacher = models.Teacher.objects.filter(id__lte=1)#过滤 小于等于 student = models.Student.objects.filter(id__range=[1,4])#过滤 小于
4.排除
#排除 #除了name=花开富贵的，其他的都查询出来 teacher = models.Teacher.objects.exclude(name='花开富贵')
5.多条件查询
#and where id = 1 and name = '魏无羡' teacher = models.Teacher.objects.filter(id=1,name='魏无羡') #or操作 #导入from django.db.models import Q #where id = 1 or name = 魏无羡 teacher = models.Teacher.objects.filter(Q(id=1) | Q(name='魏无羡'))#or 只要条件满足 就把数据都查询出来 #where id = 1 and name = '魏无羡' teacher = models.Teacher.objects.filter(Q(id=1) & Q(name='魏无羡'))#and 条件同时满足，查询数据 #where id = 1 and name != '魏无羡' teacher = models.Teacher.objects.filter(Q(id=1) & ~Q(name='魏无羡'))#and 取反