【Django】QuerySet的分页和排序

数据查询分页功能和排序功能大家都很熟悉，本文以一个小例子介绍一下Django后台实现

id依次从6到1

[

{

"detail": "this is test",

"CreateTime": "2016-05-22 00:06:36",

"ModifyTime": "2016-05-22 00:06:36",

"IsDelete": "False",

"Type": "test",

"id": "6",

"idUser_id": "1"

{

"detail": "this is test",

"CreateTime": "2016-05-22 00:06:17",

"ModifyTime": "2016-05-22 00:06:17",

"IsDelete": "False",

"Type": "test",

"id": "5",

"idUser_id": "1"

{

"detail": "this is test",

"CreateTime": "2016-05-22 00:06:17",

"ModifyTime": "2016-05-22 00:06:17",

"IsDelete": "False",

"Type": "test",

"id": "4",

"idUser_id": "1"

{

"detail": "this is test",

"CreateTime": "2016-05-22 00:06:16",

"ModifyTime": "2016-05-22 00:06:16",

"IsDelete": "False",

"Type": "test",

"id": "3",

"idUser_id": "1"

{

"detail": "this is test",

"CreateTime": "2016-05-22 00:06:15",

"ModifyTime": "2016-05-22 00:06:15",

"IsDelete": "False",

"Type": "test",

"id": "2",

"idUser_id": "1"

{

"detail": "this is test",

"CreateTime": "2016-05-22 00:06:12",

"ModifyTime": "2016-05-22 00:06:12",

"IsDelete": "False",

"Type": "test",

"id": "1",

"idUser_id": "1"

}

]

分页显示

分页有两个重要的参数，一个是每页显示的记录条数，一个是页码。

数据表查询主体代码，实现比较简单，就不解释太多，直接看代码

稍微提醒下的两点，网上很多文章都介绍了

1、分片代码lUserLogs[start:end]，这样书写只会从数据库中获取onePageCount数据，不会获取所有数据

2、lUserLogs.count()方式统计总数，不要用len（lUserLogs），前者是select count(*)语法，后者会返回整个查询结果集

分页获取第一页

onePageCount表示单页个数，默认为20，page表示页码，默认为1

GET http://127.0.0.1:8000/UserLog/?onePageCount=2&page=1

-- response --

200 OK

Date: Sun, 22 May 2016 04:07:04 GMT

Server: WSGIServer/0.1 Python/2.7.10

Vary: Cookie

X-Frame-Options: SAMEORIGIN

Content-Type: application/json

Set-Cookie: csrftoken=MA0QfFh87zllpjQT0BLuPB16F7WAOiH8; expires=Sun, 21-May-2017 04:07:04 GMT; Max-Age=31449600; Path=/

[{"detail": "this is test", "CreateTime": "2016-05-22 00:06:36", "ModifyTime": "2016-05-22 00:06:36", "IsDelete": "False", "Type": "test", "id": "6", "idUser_id": "1"}, {"detail": "this is test", "CreateTime": "2016-05-22 00:06:17", "ModifyTime": "2016-05-22 00:06:17", "IsDelete": "False", "Type": "test", "id": "5", "idUser_id": "1"}]

分页获取第二页

GET http://127.0.0.1:8000/UserLog/?onePageCount=2&page=2

-- response --

200 OK

Date: Sun, 22 May 2016 04:11:07 GMT

Server: WSGIServer/0.1 Python/2.7.10

Vary: Cookie

X-Frame-Options: SAMEORIGIN

Content-Type: application/json

Set-Cookie: csrftoken=MA0QfFh87zllpjQT0BLuPB16F7WAOiH8; expires=Sun, 21-May-2017 04:11:07 GMT; Max-Age=31449600; Path=/

[{"detail": "this is test", "CreateTime": "2016-05-22 00:06:17", "ModifyTime": "2016-05-22 00:06:17", "IsDelete": "False", "Type": "test", "id": "4", "idUser_id": "1"}, {"detail": "this is test", "CreateTime": "2016-05-22 00:06:16", "ModifyTime": "2016-05-22 00:06:16", "IsDelete": "False", "Type": "test", "id": "3", "idUser_id": "1"}]