Home Database Mysql Tutorial sqlServer使用ROW_NUMBER时不排序

sqlServer使用ROW_NUMBER时不排序

Jun 07, 2016 pm 04:19 PM
sqlserver use sort

--1.看到NHibernate是这样写的分页,感觉写起来比较容易理解(应该不会有效率问题吧?) --with只是定一个别名? [sql] 代码如下 with query as (selectROW_NUMBER() over(order by (select 0)) AS ROWNUM, * FROM Product) select * from query where ROWNUM BET

   --1.看到NHibernate是这样写的分页,感觉写起来比较容易理解(应该不会有效率问题吧?)

  --with只是定一个别名?

  [sql]

 代码如下  

with query as (select ROW_NUMBER() over(order by (select 0)) AS ROWNUM, * FROM Product) 
select * from query where ROWNUM BETWEEN 5 AND 10

  --2.ROW_NUMBER必须指写over (order by **),有时我根本就不想排序,想按原始顺序(排序也是要时间的嘛)

  --方法就是:

 代码如下  

select ROW_NUMBER() over(order by (select 0)) AS ROWNUM,* FROM Product

  排序 就是 :

 代码如下  

select Row_number() over(order by Oper_Date desc) AS ROWNUM,* FROM Product

  接着我们来看一个实例ROW_NUMBER排序实例

  1使用row_number()函数进行编号:如

 代码如下  

select email,customerID, ROW_NUMBER() over(order by psd) as rows from QT_Customer

  原理:先按psd进行排序,排序完后,给每条数据进行编号。

  2.在订单中按价格的升序进行排序,并给每条记录进行排序

  代码如下:

 代码如下  


 select DID,customerID,totalPrice,ROW_NUMBER() over(order by totalPrice) as rows from OP_Order

  3.统计出每一个各户的所有订单并按每一个客户下的订单的金额 升序排序,同时给每一个客户的订单进行编号。这样就知道每个客户下几单了。

  如图:

sqlServer使用ROW_NUMBER时不排序 三联

  代码如下:

 代码如下  

 select ROW_NUMBER() over(partition by customerID  order by totalPrice) as rows,customerID,totalPrice, DID from OP_Order

  4.统计每一个客户最近下的订单是第几次下的订单。

  代码如下:

 代码如下  


1 with tabs as
2 (
3 select ROW_NUMBER() over(partition by customerID  order by totalPrice) as rows,customerID,totalPrice, DID from OP_Order
4 )

6 select MAX(rows) as '下单次数',customerID from tabs group by customerID

 

  5.统计每一个客户所有的订单中购买的金额最小,而且并统计改订单中,客户是第几次购买的。

  如图:

sqlServer使用ROW_NUMBER时不排序

  上图:rows表示客户是第几次购买。

  思路:利用临时表来执行这一操作

  1.先按客户进行分组,然后按客户的下单的时间进行排序,并进行编号。

  2.然后利用子查询查找出每一个客户购买时的最小价格。

  3.根据查找出每一个客户的最小价格来查找相应的记录。

 代码如下  

 

with tabs as
(
select ROW_NUMBER() over(partition by customerID  order by insDT) as rows,customerID,totalPrice, DID from OP_Order
)
select * from tabs
 where totalPrice in 
           (
           select MIN(totalPrice)from tabs group by customerID
           )

  5.筛选出客户第一次下的订单。

  思路。利用rows=1来查询客户第一次下的订单记录。

  with tabs as

  (

  select ROW_NUMBER() over(partition by customerID order by insDT) as rows,* from OP_Order

  )

  select * from tabs where rows = 1

  select * from OP_Order

  6.rows_number()可用于分页

  思路:先把所有的产品筛选出来,然后对这些产品进行编号。然后在where子句中进行过滤。

  7.注意:在使用over等开窗函数时,over里头的分组及排序的执行晚于“where,group by,order by”的执行。

  如下代码:

 代码如下  


1  select 
2  ROW_NUMBER() over(partition by customerID  order by insDT) as rows,
3  customerID,totalPrice, DID
4   from OP_Order where insDT>'2011-07-22'

Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

AI Hentai Generator

AI Hentai Generator

Generate AI Hentai for free.

Hot Article

R.E.P.O. Energy Crystals Explained and What They Do (Yellow Crystal)
2 weeks ago By 尊渡假赌尊渡假赌尊渡假赌
Repo: How To Revive Teammates
4 weeks ago By 尊渡假赌尊渡假赌尊渡假赌
Hello Kitty Island Adventure: How To Get Giant Seeds
4 weeks ago By 尊渡假赌尊渡假赌尊渡假赌

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

How to solve the problem that the object named already exists in the sqlserver database How to solve the problem that the object named already exists in the sqlserver database Apr 05, 2024 pm 09:42 PM

For objects with the same name that already exist in the SQL Server database, the following steps need to be taken: Confirm the object type (table, view, stored procedure). IF NOT EXISTS can be used to skip creation if the object is empty. If the object has data, use a different name or modify the structure. Use DROP to delete existing objects (use caution, backup recommended). Check for schema changes to make sure there are no references to deleted or renamed objects.

How to import mdf file into sqlserver How to import mdf file into sqlserver Apr 08, 2024 am 11:41 AM

The import steps are as follows: Copy the MDF file to SQL Server's data directory (usually C:\Program Files\Microsoft SQL Server\MSSQL\DATA). In SQL Server Management Studio (SSMS), open the database and select Attach. Click the Add button and select the MDF file. Confirm the database name and click the OK button.

What to do if the sqlserver service cannot be started What to do if the sqlserver service cannot be started Apr 05, 2024 pm 10:00 PM

When the SQL Server service fails to start, here are some steps to resolve: Check the error log to determine the root cause. Make sure the service account has permission to start the service. Check whether dependency services are running. Disable antivirus software. Repair SQL Server installation. If the repair does not work, reinstall SQL Server.

How to check sqlserver port number How to check sqlserver port number Apr 05, 2024 pm 09:57 PM

To view the SQL Server port number: Open SSMS and connect to the server. Find the server name in Object Explorer, right-click it and select Properties. In the Connection tab, view the TCP Port field.

How to recover accidentally deleted database in sqlserver How to recover accidentally deleted database in sqlserver Apr 05, 2024 pm 10:39 PM

If you accidentally delete a SQL Server database, you can take the following steps to recover: stop database activity; back up log files; check database logs; recovery options: restore from backup; restore from transaction log; use DBCC CHECKDB; use third-party tools. Please back up your database regularly and enable transaction logging to prevent data loss.

Where is the sqlserver database? Where is the sqlserver database? Apr 05, 2024 pm 08:21 PM

SQL Server database files are usually stored in the following default location: Windows: C:\Program Files\Microsoft SQL Server\MSSQL\DATALinux: /var/opt/mssql/data The database file location can be customized by modifying the database file path setting.

How to delete sqlserver if the installation fails? How to delete sqlserver if the installation fails? Apr 05, 2024 pm 11:27 PM

If the SQL Server installation fails, you can clean it up by following these steps: Uninstall SQL Server Delete registry keys Delete files and folders Restart the computer

How to use Baidu Netdisk app How to use Baidu Netdisk app Mar 27, 2024 pm 06:46 PM

Cloud storage has become an indispensable part of our daily life and work nowadays. As one of the leading cloud storage services in China, Baidu Netdisk has won the favor of a large number of users with its powerful storage functions, efficient transmission speed and convenient operation experience. And whether you want to back up important files, share information, watch videos online, or listen to music, Baidu Cloud Disk can meet your needs. However, many users may not understand the specific use method of Baidu Netdisk app, so this tutorial will introduce in detail how to use Baidu Netdisk app. Users who are still confused can follow this article to learn more. ! How to use Baidu Cloud Network Disk: 1. Installation First, when downloading and installing Baidu Cloud software, please select the custom installation option.

See all articles