1. 条件搜索

   使用条件搜索时，可以直接使用filter链来过滤掉满足条件的记录，因为每次filter()的结果仍然是一个QuerySet,因此可以根据参数有无，来添加filter。

   先不添加任何搜索条件获取一个QuerySet。

invoice_heads = InvoiceHead.objects.filter(
                resource_uid=resource_uid,
                status="Y",
                user_id=user_id,
            )

1) 等值比较

 if invoice_type is not None:
		invoice_heads = invoice_heads.filter(invoice_type=invoice_type)

2) 不等于比较

  大于等于__gte, 小于等于__lte。

  if end_date is not None:
                invoice_heads = invoice_heads.filter(invoice_date__lte=end_date)

3) 完整案例

  将每个需要搜索的字段先判断一下是不是None,如果不是None,那么就在queryset后面在拼接.filter() ,实现条件搜索过滤。

class OpenedInvoiceQuery(BaseView):

    def get(self, request, resource_uid=None):
        r = Result()
        using = self.get_partner(request)
        try:
            student = self.student_auth(request)
            user_id = student['id']
            invoice_type = request.GET.get("invoice_type")
            invoice_code = request.GET.get("invoice_code")
            invoice_no = request.GET.get("invoice_no")
            start_date = request.GET.get("start_date")
            end_date = request.GET.get("end_date")
            invoice_status = request.GET.get("invoice_status", 0)
            size = int(request.GET.get("size", 10))
            page = int(request.GET.get("page", 0))

            invoice_heads = InvoiceHead.objects.filter(
                resource_uid=resource_uid,
                status="Y",
                user_id=user_id,
            )
            if invoice_type is not None:
                invoice_heads = invoice_heads.filter(invoice_type=invoice_type)
            if invoice_code is not None:
                invoice_heads = invoice_heads.filter(invoice_code=invoice_code)
            if invoice_no is not None:
                invoice_heads = invoice_heads.filter(invoice_no=invoice_no)
            if invoice_status is not None:
                invoice_heads = invoice_heads.filter(red_flag=invoice_status)
            if start_date is not None:
                invoice_heads = invoice_heads.filter(invoice_date__gte=start_date)
            if end_date is not None:
                invoice_heads = invoice_heads.filter(invoice_date__lte=end_date)
            r.data_count = len(invoice_heads)
            page_obj = Paginator(invoice_heads, size)
            page_data = page_obj.get_page(page)
            res = page_data.object_list
            data = []
            for i in res:
                d = InvoiceHeadSerializers(i).data
                line = InvoiceLine.objects.filter(head=i).first()
                d["main_goods_name"] = line.goods_name
                d["total_price_with_tax"] = i.amount + i.total_amount
                data.append(d)
            r.data = data
        except Exception as e:
            r.error(e)
        return self.s_result(r)

2. 模糊匹配

   在django的orm中，可以使用__icontains 来表示mysql里的like “%%”
   匹配code,key,goods_name,simple_name:

from django.db.models import Q  

 
row = InvoiceProductCategories.objects.using("admin") \
            .filter(~Q(rate1=None),
                    goods_name__icontains=goods_name,
                    simple_name__icontains=simple_name,
                    code__icontains=code,
                    key__icontains=key)

不等于使用~Q，在默认的不等于None中，需要把~Q放到filter()的最前面，要不然会编译不通过。